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The research deals with the study of the quality indicators in the productive process and its use for the consuming market, for two types of ores: industrial sand and crushed stone. Companies who represent the profile of the São Paulo producing market in its respective modalities well produce the selected cases. The development of the studies have to be, for the application of consistent methodological models of the fundamentals of the Engineering of Quality, especially how much to the statistical control of processes and its trustworthiness, of form that the results of the research can serve as referential in the boarding for other generic cases of the mineral industry.

Jan 1, 2003

By A. C. C. Pacheco, L. C. Bertolino, M. L. Torem

On account of geological characteristics, Brazil is a country of large deposits of high quality kaolin, with the larger ones being located in its northern region. In the last years, kaolin beneficiation and production area is receiving great investments, aiming at a high quality kaolin production to be used in the paper industry, mainly intended for the foreign market. After the conclusion of expan- sion programs and with the advent of new production areas, Brazil is very soon expected to come in second place in the kaolin world production ranking.

Jan 1, 1998

By Glenn M. Boyce, Timothy R. Coss

Microtunneling first appeared with some regularity in the United States in 1987. Until then, only Japan and Germany utilized this method of construction. Its high costs initially limited its application to special situations. The last ten years have seen the use of new pipe materials, new machines, new cutterheads, new techniques, and an average growth of30 percent each year. This paper documents the growth and changes that have occurred with microtunneling. Based on current industry practices and advances from abroad, this paper postulates what the next ten years may hold.

Jan 1, 1997

By V. R. Degner

Development of large mechanical flotation machines during the past fifteen years. This success was a contributing factor in recognizing the value in a systematic and rational means of optimizing the flotation circuit, where the preferred circuit arrangement is based on both economic and metallurgical performance considerations applied to a relatively small number of flotation machines. Flotation kinetics and effective pulp residence time models have been incorporated into a computer program, described in this paper, which has proven to be an effective analytical tool to quantitatively relate flotation process parameters, such as feed tonnage and grade, solids concentration, and reagent strategy, to flotation circuit arrangement, machine size and operating condition.

Jan 1, 1993

By Chen Bingchen, Ma Shaojian

A new magnetic liner, with unique magnetic circuit and novel structure designs, was developed. It was characterized by light weight, low noise, as well as corrosive and abrasive resistance. The wear rate of the magnetic liner was one twentieth and one ninth those of the manganese-alloy steel and rubber ones respectively. The forming mechanism of the protective layer and that of influencing factors on magnetic liners were also investigated. The research results could not only instruct using magnetic liner, but also widen their application.

Jan 1, 1995

By K. R. Johnejack, R. Quintanar, P. Lapointe

Chino Mines Company has investigated effects from historical mining to sediment along Hanover and Whitewater Creeks. Concentrations of metals were statistically stratified for risk assessment. Stratification by size was more prevalent than by depth, with concentrations higher in the fines. Concentrations with depth were mixed, but overbanks showed more stratification with higher concentrations in the surface. Members of a geomorphic feature type generally were not stratified. However, geomorphic features were stratified by type, with the active channel and bars being the most alike and the overbanks being the most different. Only a few metals showed decreasing concentrations with distance downstream.

Jan 1, 2002

The last twenty years of development in Process Mineralogy are reviewed. Since the milestone review by Henley in 1983, which projected the concept and suggested closer working relations between mineral processing and mineral science, the second generation (1983-2003) has made significant progress. Examples are to be found in improved sampling and high-confidence flotation testing, and in automated quantitative mineral measurement. The recent addition of end-member studies has provided a clearer view of the overall ore mixture milled from its constituent geological components. In all, better predictive abilities have resulted from these improvements to Process Mineralogy. These improvements have led to more significant business impacts in mineral resource characterization, and in optimization of existing concentrator operations.

Jan 1, 2004

By MSHA

Not quite a year ago, during a speech to a group of mining professionals in Washington, DC, the subject centered around the long-range importance of conducting research projects and how much that research needs to specifically apply to health and safety matters in our industry. The point was made about the critical need to work together with government, private industry, labor organizations and academia speaking with a unified voice as we all march into the future together. The fundamental benefits of competitive research were mentioned -- to improve our quality of life, to develop our energy resources, to achieve a safe and healthy environment and to ensure long-term economic growth. Very importantly, emphasis was given to the natural link that makes my agency, the Mine Safety and Health Administration, and the National Institute for Occupational Safety and Health -- NIOSH -- the beneficiaries of each other's findings.

Jan 1, 1999

By K. Nielsen

This paper is based on two recently (2002) published reports: - "Breaking New Ground". Final report on the Mining, Minerals, and Sustainable Development Project (MMSD). - "2002 Sustainability Reporting Guidelines". Published by the Global Reporting Initiative (GRI). The GRI guidelines can be applied in all kinds of industries and other organizations, whereas the MMSD project report is sector specific. However, both reports center on the three pillars of sustainability. The performance indicators as they are presented in the GRI guidelines have been assessed and compared with the sector specific arguments in the MMSD report. Based on this evaluation, the paper points at some indicators that may be useful in the start-up phase of sustainability reporting, seen from the perspective of the aggregate industry in an industrialized North European country with increasing environmental awareness and pressure on natural resources.

Jan 1, 2003

By R. Renzoni, S. Belboom, F. Tourneur, A. Léonard

"Construction is a field which is concerned by environment. Tools as environmental product declarations are increasingly often used to compare several products and to take account of the environmental sphere in the choice. Environmental declarations of Belgian bluestone and sandstone products were realized in accordance with the ISO standards and following the standard NF P 01-010. The main goals of these studies were to obtain Belgian environmental product declarations to strengthen existing databases and to provide defences against Asian competition. Indeed, competition with China for bluestone products and with India for sandstone pavement is very important due the fact of the very competitive prices for foreign products. The impacts on climate change, resources and acidification of the sole transport were taken into account for foreign products"

Jan 1, 2011

By P. R. Khangoankar, S. Devasahayam

An experimental study of the particle charac¬teristics of the magnesium carbonate crystals formed by the reaction between magnesium chloride and sodium bicarbon¬ate at different temperatures is described. The rate of growth of magnesium carbonate crystals for any constant tempera¬ture is established, and this rate of growth is related to the degree of supersaturation at the given temperature. The activation energy calculated using empirical constants de¬rived from the relationship between the crystal growth rate and supersaturation, is indicative of a surface-reaction mechanism.

Jan 1, 1996

By G. M. Riddle

As an important part of the concept validation phase of the MX Advanced ICBM development program, Air Force System Command's Intercontinental Ballistic Missiles (ICBM) Program Office developed and demonstrated large trenching and cast-in-place equipment for placing many miles of buried concrete tunnel rapidly and economically. A tunnel or "buried trench" containing a mobile ICBM is one of the candidate basing models for MX. Upon remote command, the cannister housing the missile would break out of its concrete tunnel and earth overburden by erecting itself to a suitable angle and then launching the missile. The ICBM Program Office developed two each trenchers, cast-in-place machines, and breakout mechanisms, as well as a mobile concrete truck unloader. The machines were demonstrated in varying soil conditions in the southwest US. The breakout mechanisms were demonstrated nearby as well. This chapter describes the development program, the machines, and the demonstrations. No manuscript received

Jan 1, 1979

By C. Vasquez, A. Nieto

In past drilling programs for a multi-seam Texas lignite reserve, extensive e-log data was collected; however, little laboratory analyses were performed. As a cost and time saving incentive, sampling of lignite was intensified. In a recent drilling program in east-central Texas, detailed laboratory analyses and e-log information was gathered on a multi-seam lignite reserve of the upper Wilcox Group. This data will undergo statistical and geostatistical techniques in an attempt to discern whether or not predicted Ash and Btu/lb values can be derived from the e-log gamma-density relationships. Final characterization of the dataset will be used in a geostatistical model of that reserve. This model will be the basis for further geological investigations and mine planning.

Jan 1, 2004

By Pertti Koivistoinen

There are many grinding schools in the mining world, which claim their grinding method to be the best possible - and still the methods concerned vary a great deal. Some of them have multi- stage crushing and only single stage grinding while in others crushing may be nominal, but grinding can be very complicated. - In this presentation firstly the nine most common comminution circuits will be analyzed. Then results from a pilot scale test series will be reviewed, in which nickel ore ground by four different comminution methods was fed to a common flotation treatment.

Jan 1, 1995

By Donald C. Trueblood

Since the Surface Mining Control and Reclamation Act (SMCRA) was passed in 1977, coal mine reclamation has been restricted from utilizing bluff-1ike features in permanent reclamation. This restriction is based on those provisions of SMCRA which require the elimination of all highwalls. In 1987, the Wyoming Mi ni ng Association began an effort to acquire the ability for coal mines to utilize bluffs in permanent reclamation for the purpose of enhancing the post-mining land use. The regulatory reform approach being uti1ized includes formation of a work group with members from industry, government, agriculture, and environmental organizations to prepare a proposal. Advantages of this approach are discussed.

Jan 1, 1989

By M. García-Vásquez

In Peru, the third destination in worldwide exploration based on expenditure, mining conflicts have spread dramatically over the last decade. Mining companies need to create new initiatives to avoid social conflicts and strengthen the social capital needed to keep mining in a country with proven mineralogical riches. This document provides information about a research project that explored the opinions and experiences of a resource many times overlooked by companies: the human resource. Over 30 surveys were conducted among professionals working at mines in the Peruvian mining industry, in different departments and from different organizational levels. Mining employees acknowledged that they play an important role in the development of company-community relationships and gave their impressions about initiatives implemented by international mining companies in Peru. Mining employees also provided their recommendations to succeed in a location where cultural differences have not been properly considered.

Jan 1, 2011

By Z. Kowalski

Landfilling of waste causes the degradation of natural environment, not only due to land occupation, but also due to pollution of air, water and soil. The flotation waste from zinc-lead industry also poses such problem. There is a need to find the way to utilise substantial amount of these wastes and backfilling seems to be a good solution. Recently, in Poland only sand was used for backfilling. However, it will be more beneficial to substitute the sand with the industrial solid waste, especially flotation waste. The tests were performed in the laboratory to examine the use of flotation waste as a main ingredient for backfilling. The use of flotation waste is possible only when it is combined with other waste with specific bonding properties, especially regarding the prevention of leakage. The outcome of tests shows that flotation waste combined with cement and fly ashes can be used as a backfilling material. This paper presents the preparation of flotation waste for using it for backfilling.

Jan 1, 2006

By Emmanuel J. Voulgaris

The ?Milos Conferences? is an activity of the non-profit organization ?Milos Conference Center - George Eliopoulos?, located on the island of Milos, Greece. The objective of the ?Milos Conferences? is to create the conditions for interaction among different disciplines of academia and industry, and dissemination of the cutting edge between scientific and technological development. The young scientists are our special aim. The governing body of the ?Milos Conferences? is the ?Milos Conferences Council?. The president of the Council is Mrs. Kitty Kyriacopoulos - founder of the ?Milos Conference Center - George Eliopoulos?, and the members are from academia and industry. The planning and the organization of all conferences are carried out by the ?Heliotopos Professional Congress Organizers? in Athens. The venue is always the ?Milos Conference Center - George Eliopoulos? on the island of Milos. The ?Milos Conferences? comprise of different conference series, each devoted to a general subject. This book covers the proceedings of the ?International Conference on Sustainable Development Indicators in the Mineral Industries?, (SDIMI), a conference of the series under the general title ?Restoring the Natural Balance?.

Jan 1, 2003

By M. W. Chanda

This paper presents the development of a rock-creep measuring apparatus using air as the initial pressure source. Servo-controlled machines can and have been used for time-dependent property tests. However, the long-term nature of some tests makes essential the complete independence of stress-maintaining equipment from main power sources or continuously running hydraulic pumps. The main objective of this paper is the development of a creep testing machine that is free from interference arising through power supply interruptions or mechanical maintenance normally associated with many compression testing machines. To achieve this, a compressed-air power source was used to drive a compression ram. A few trial results obtained and analyzed using the transient creep law are in reasonable agreement with the general creep law.

Jan 1, 1993

By R. Trottier, B. H. Kaye

Characterizing the structure of such open-structured dusts such as diesel soot and those present in welding fumes plus any other dusts which were initially formed by precipitation or agglomoration of subsidiary units in a flame process has always been a difficult task. Recently, scientists have been able to use the concepts of fractal geometry to model the growth of diesel soot and fume fine particles and characterize their structure using fractal dimensions. The measured fractal dimension of a diesel exhaust at various levels of scrutiny can be used to study the health hazards posed by the soot. Thus, the fractal dimensions of the overall structure can be related to the dynamics of the dust both empirically and theoretically. In this communication, the use of fractal dimensions to describe the structure of smoke and fine particles which pose a respirable hazard are reviewed. Experimental studies linking the measured fractal dimensions of the fine particles to dynamics of the fine particles in respirators and in the lung are outlined.

Jan 1, 1987