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P. H. Dudley, Yew York, N. Y. (communication to the Secretary*) :—The characteristics of Professor Home's metallurgical papers are, that he is able, from the mass of confusing evidence on the subject, to make an analysis and present hypothetical and essential principles in concrete form for consideration and discussion. I can appreciate, from the practical side of the subject, the labor of collecting and investigating the data which was essential to prepare the paper. Much of it necessarily came from material of preceding years of manufacture in which time was allowed for chemical reactions of the re-carburizer, and for the elimination of the oxidation-products before teeming the ingots. This practice gave a favorable time-element to free the metal from slag and other impurities— a requisite condition for the production of sound steel in the ingots. But, in allowing them to become cold before they were charged into the furnace, a subsequent time-element entered as a detrimental factor in the development of the pipe or shrinkage-cavities, which gave an ingot-structure deficient in soundness, at least in the upper portion. (The term slag is used in a general rather than in a strictly technical sense.) Traces of manganese sulphide are often associated with manganese silicates in the same thread or seam, and at other places they are separate and distinct. Interpretations from material thus manufactured must be made with due allowances for the methods of fabrication and the requirements of service. The only way we now have to estimate what the degree of soundness of the ingot-structure was, in the early foreign and American manufacture of steel rails, is by examination of the worn and failed material after years of service. We must remember also that the poorest material was long since consigned to the scrap-heap without any full record of its history. The rails from a given ingot cannot now be identified ; and in many

Jan 1, 1909

By Heric Henrique Souza e Silva, Johne Jesus Mol Peixoto, Natalia Barros Barony, Itavahn Alves da Silva, Weslei Viana Gabriel, Carlos Antonio da Silva, Varadarajan Seshadri

In this work the circulation rates have been determined in a 1:7.5 scale physical model of RH reactor (Ruhrstal Heraeus) and using oil/water and oil/zinc chloride solution to simulate steel melt/slag in the prototype with the objective of evaluating the influence of density and viscosity on the entrainment of oil simulating slag. A technique based on strain gage bridge and particle image velocimetry was developed to assess the circulation rate, as the usual tracer method is not feasible due to the presence of chloride ions in ZnCl2. The critical velocity and critical diameter of oil drops for slag (oil) entrainment in water/oil and ZnCl2/oil systems were estimated using equations from the literature. Due to the difference in density, the ZnCl2/oil system, showed a critical velocity that is 28% higher than the silicone oil/water system while the maximum size of the entrained droplets was about 65% lower than that for water/oil system.

Mar 1, 2017

By R. H. Nicholas

Shuttle cars have undeniably proved their worth as a means of transporting coal underground; however, several factors have arisen in connection with their possible improvement. This report .discusses the effect of shuttle cars that employ rough-tread and smooth-tread tires on mine roadbed, the amount of dust thrown into suspension by the use of such tire treads, and the service rendered by each type of tire. Involved, also, in this study are observations on the use of different amounts of calcium chloride on the haulageways.

Jan 1, 1949

By W. H. Davitt

While it is true that taxes, especially income taxes, whether they be federal, state, or local, are not usually thought of as a "cost" of doing business, it is equally true that these tax costs do reduce the distributable profits just as much as the cost of power, supplies, or labor. Therefore, the consideration given to taxes is often as important as that given to other costs. Hopefully you will recognize that, within certain limits, taxes can be controlled to an economic advantage. The tax laws as now imposed are quite complex. Many of these laws and the regulations thereunder involve many factual determinations, technical considerations, and specialized valuations that can best be made by people trained in the specific area concerned. A substantial amount of a tax liability turns on the proper consideration given to issues involving facts and principles which are peculiarly engineering in nature. The importance of these "engineering" issues in tax administration has been significantly increased in recent years by our rapidly advancing technology, automation, stepped-up mineral and oil exploitation, new industries such as electronics and nuclear power, and the extension of percentage depletion to all minerals. These specialized requirements incorporated in the law are so technical that full consideration can not be given by people with a non-engineering background.

Jan 7, 1974

By T. Fernandez, V. Juchen, C. Petter, F. Cantini, V. Lenz, V. I. Araújo, R. Petter, R. Darrigo, A. Young, I. G. da Costa, J. Oppermann

There are many methods to estimate costs quickly. One of these is the Parametric Method, where costs are estimated from general algorithms (or curves). Derived from an original tool based on the O’Hara model, a software called MAFMINE was developed. MAFMINE is based on parametric models to estimate investment and operational costs in mining. The software itself is based on the use of a computer model known as client-server. However, the model needs new inputs from advances made by the mining industry, mainly in terms of electrification, automation, digital transformation and preconcentration to face Environmental, Social and Governance (ESG) concerns. Thus, this work was to prepare a new core module ready to incorporate the new technologies aiming to deliver operation and capital costs associated with environmental impact mitigation. The tool generates an order of magnitude estimate for CAPEX and OPEX to establish a very first Discounted Cash Flow (DCF) in a mining venture. For quick evaluations, at a preliminary level, the results are very promising.

Mar 2, 2022

By Isadora Dias Perez

Em vista da crescente geração de efluentes contendo metais, busca-se por técnicas sustentáveis capazes de recuperá-los, devido à toxicidade e ao valor econômico agregado. Os metais ainda contribuem com a poluição dos recursos hídricos. Desta maneira, o presente trabalho investiga a adsorção dos metais presentes num efluente produzido na mineração (licor) do níquel, através da resina quelante de troca iônica Dowex XUS43605. Os experimentos foram realizados em bateladas, variando pH, para verificar a captação pela resina do alumínio, cobalto, cromo, cobre, ferro (III), magnésio, manganês, níquel e zinco presentes no licor. A concentração dos metais na solução foi obtida pela técnica de espectrometria de fluorescência de raios-x por energia dispersiva (EDX). Os resultados mostram a capacidade de remoção dos metais pela resina, destacando 83% de adsorção do cobre e 7% do níquel, considerando 2,0 pH e tempo de contato 2h. Portanto, o estudo demonstra que a resina de troca iônica pode ser utilizada para tratar efluentes, em especial, de mineração.

Aug 17, 2017

By Eric P. Bregman

As part of an on-going effort to improve water quality and reduce discharge into Boston Harbor, the Massachusetts Water Resources Authority (MWRA) East Boston Branch Sewer Relief Project was designed under a Federal mandate from the United States Environmental Protection Agency (EPA) to upgrade the aging sewer system, increase system storage and greatly reduce the volume of combined sewer overflows into the Harbor. The project scope of work includes the installation of over 2 miles (11,800 linear feet) of 36-inch and 66-inch diameter sewer relief piping, twenty (20) temporary shafts and an approximate 100 foot open cut section, located within the densely populated neighborhood of East Boston, Massachusetts. This area is a former marshland backfilled in the early to mid 1800?s where busy commercial streets co-mingle with thickly settled residential houses. The subsurface conditions present within Boston?s complex geology include the presence of subsurface contamination as well as complex networks of underground utilities. Additional site limitations included low headroom, noise, and traffic restrictions. Together these limitations required the design of individual earth support systems, tailored for each shaft location. Moreover, challenging subsurface conditions identified during construction required design modifications to minimize cost and schedule impacts related to construction dewatering, treatment of contaminated groundwater, internal bracing, and utility relocations. This paper provides a case history of the Geo-structural design and performance of various earth support techniques utilized to construct jacking and receiving shafts designed to launch and receive two (2) micro-tunnel boring machines (MTBM) and to support the construction of new deep shaft structures in an urban coastal area.

By Eric P. Bregman, Franklin M. Grynkewicz, John E. Regan

"As part of an on-going effort to improve water quality and reduce discharge into Boston Harbor, the Massachusetts Water Resources Authority (MWRA) East Boston Branch Sewer Relief Project was designed under a Federal mandate from the United States Environmental Protection Agency (EPA) to upgrade the aging sewer system, increase system storage and greatly reduce the volume of combined sewer overflows into the Harbor. The project scope of work includes the installation of over 2 miles (11,800 linear feet) of 36-inch and 66-inch diameter sewer relief piping, twenty (20) temporary shafts and an approximate 100 foot open cut section, located within the densely populated neighborhood of East Boston, Massachusetts. This area is a former marshland backfilled in the early to mid 1800’s where busy commercial streets co-mingle with thickly settled residential houses.The subsurface conditions present within Boston’s complex geology include the presence of subsurface contamination as well as complex networks of underground utilities. Additional site limitations included low headroom, noise, and traffic restrictions. Together these limitations required the design of individual earth support systems, tailored for each shaft location. Moreover, challenging subsurface conditions identified during construction required design modifications to minimize cost and schedule impacts related to construction dewatering, treatment of contaminated groundwater, internal bracing, and utility relocations.This paper provides a case history of the Geo-structural design and performance of various earth support techniques utilized to construct jacking and receiving shafts designed to launch and receive two (2) micro-tunnel boring machines (MTBM) and to support the construction of new deep shaft structures in an urban coastal area."

Jan 1, 2017

The approach to this subject is a very general one, but an attempt has been made to cover briefly a very wide field in the nationally important job of manufacturing iron for the iron and steel industry.Some historical data concerning the development of the furnace itself from early days have been followed by the modern ideas on raw materials and their beneficiation. Recent furnace design and modern auxiliaries have been given attention with, finally, some developments in practical operation.HISTORICALWhen dealing with such large 'and costly operating units as blast furnaces, there is not the same opportunity for research in design as in most other metallurgical processes. Over past generations the development of furnace design, or "lines" as it is usually termed, as well as most radical operating changes, has been very gradual.However, there have been some periods of rapid progress due to revolutionary changes. One such was the adoption of the steam engine for blowing and charging operations, and also, during this same era, about 1750, coke was first used as fuel in place of charcoal. Another revolutionary change came some 100 years later, when heating the blast became usual practice.Since then there have been great improvements in mechanical equipment and in the preparation of raw .materials. These factors, together with a better understanding of what happens inside the furnace, have led to the development of those large mechanically operated structures which are the most modern in blast furnace design.For many, years America has led the world in pig iron production and in furnace development, so that American design and practice is now recognised almost as standard. This type of furnace replaced the older stacks in England, Russia, Germany, South Africa and India, as well as here in Australia.

Jan 1, 1947

By R. MacRosty, R. Pula, P. Gebski, W. Braun

"This paper provides a progress update on three tapblock monitoring technologies that Hatch has been developing with our clients for non-ferrous smelting furnaces.The Tapblock Diagnostic System (TDS) is an advanced on-line monitoring system that uses temperature data along with embedded thermal model results to evaluate the condition of a tapblock over its campaign life. Hatch recently installed a second Tapblock Diagnostic System, some details of which are provided in this paper.The Tap-hole Acoustic Monitoring (TAM) system is installed on water-cooled copper tapblocks and uses the noise from the tapping channel to provide a qualitative indication of wear and deterioration of the tapping channel refractory. In addition, TAM can be used to monitor drilling and lancing performance, and potentially could also be used in the future as a guide for automatic drilling and lancing systems (Sadri et al., 2008).The third technology is the use of fibre optic sensors to measure temperature on the hot face and in the tapping channel of a tapblock. Fibre optic technology allows installation of numerous sensors in key locations where they are very sensitive to tapblock condition and also provide more extensive spatial coverage than is possible with traditional instruments. This paper provides an update on our efforts to address issues with premature failure of the sensor cables due to corrosion, and also converting the vast amount of data from the sensor cable into information that can be used by furnace operators."

Jan 1, 2014

By Jason Baird, Philip Mulligan, Caleb Baumgart

This report details the pressure variances, measured at four pressure sensors placed equidistant from the center of an airburst explosion, as the blast pressure from a single charge expands radially. Many of the empirically derived equations used for predicting the blast pressures of an explosion, assume a point source detonation and that the radial pressure expansion is equal. The authors understand that the equations used to approximate the blast pressure may not have 100 percent agreement with the observed pressure. However, during previous research at Missouri University of Science and Technology (Missouri S&T) the pressure variances had a range of 1,200 psi, between the four pressure sensors placed two feet from the center of a 1/2-pound (226.8 gram) of hand packed C4. The variances indicated that at the close distance from a suspended explosive charge the pressure does not behave as that observed from a point source.

Jan 1, 2014

By Andreas Bienz

The safety of persons from accidental explosions and fires during manufacture, storage, transport etc. of explosives, pyrotechnics, propellants, firework and ammunition is most commonly assessed according to prescriptive rule-based approach: Safety is given when all requirements which are listed in numerous regulations and directives (such as e.g. safety distances, limited quantities, protective installations etc.) are complied with. Such a deterministic prescriptive rule-based approach is quite easy to apply but has got disadvantages, however: The actual state of safety in a specific case is not explicitly and quantitatively expressed, and it is not distinguished between the endangered individuals and the whole group. As a result, the effects of the safety measures cannot be measured. This is why uneconomical and in the worst case useless safety precautions cannot be avoided. In addition, waivers are difficult to negotiate, meaningful and sound arguments for pro and con being lacking.

Jan 1, 2007

By C. H. Jr. Herty

ALMOST every metallurgist who has given the Howe Memorial Lecture has had a personal contact with the distinguished gentleman to whose honor this hour is devoted. Unfortunately for me, such personal contacts were not possible. However, in the preparation of a thesis on the open-hearth process, one of my earliest tasks was to make a survey of the literature, and it was from Professor Howe's Metallurgy of Iron and Steel that I drew a number of references to previous work which formed the foundation for my reading. In his volume there is such a complete exposition of the then current thought on the subject of slags and on their role in the elimination of phosphorus from steel that I feel no hesitation in discussing in this Howe Lecture the subject of "Slag Control." In the present era of close specification, the drive for uniformity of product, and the close inspection of the product and of the cost sheet, the utmost efforts must be made to control the steelmaking variables to the best advantage of the steel producer. One of the major variables is the slag in the furnace and its effect upon the composition and quality of the metal. What advantages are to be gained from slag control? In the broad sense the advantages must be tremendous, because the very foundations of good steel melting are based on "shaping up" the slag to a point where, with proper temperature, the heat is ready for the final additions. Every melter works toward these ends through his experience with innumerable heats of steel. The elimination of undesirable constituents such as phosphorus and sulphur is entirely a matter of slag composition and physical nature, a point well known for over half a century. The role played by the slag in assisting in proper heat transfer from roof and flame to the steel has been equally well known. In more recent years there has come the problem of oxygen control in the more accurate gaug-ing of additions for making high-grade rimmed steel for the new strip mills, and in the deoxidizing additions for grain-size control and cleanli-ness of forging steels, both carbon and alloy. In this problem the oxidiz-ing characteristics of the slag are of prime importance.

Jan 1, 1940

By Gabriela Moreira Lana

A radiação solar apresenta uma enorme variedade de aplicações de engenharia, dentre elas, a conversão em energia térmica em concentradores solares. Os tubos absorvedores dos concentradores solares podem ser recobertos por cromo negro, com o objetivo de otimizar a absorção energética e a durabilidade. Esse trabalho é parte de um estudo complexo sobre esse tipo de recobrimento. Foram desenvolvidos filmes de cromo negro por eletrodeposição sobre aço inoxidável AISI 304 e tratados termicamente a 600°C por 2 horas. Os filmes foram caracterizados antes e depois do tratamento térmico, utilizando-se microscopia eletrônica de varredura (MEV), espectroscopia de energia dispersiva (EDS) e difração de raios X a baixo ângulo de incidência (GAXRD). Além do cromo, observou-se deposição de cobalto e elementos residuais do banho eletrolítico. O estudo da estrutura cristalina mostrou formação de óxidos após tratamento térmico. Microestruturalmente, foram observados filmes com estrutura lamelar ou nodular. O estudo permitiu sugerir modificações do banho eletrolítico, do substrato e métodos adicionais de caracterização.

Aug 17, 2017

By Marvin L. Whisman

This report describes the preparation of tritium-labeled organic compounds to be used by the Federal Bureau of Mines in studying the role of certain gasoline constituents in gum-forming mechanisms. The gasoline constituents that have been investigated boil within a range of approximately 90 to 230° C. and can be classified as paraffins. naphthenes, olefins, diolefins, monocyclic aromatics, polycyclic aromatics, and organic sulfur, nitrogen,: and oxygen compounds. The technique of Wilzbach has been applied to more than 50 samples. Purification techniques have been developed that accomplish rapid and effective purification as well as removal of labile tritium in a one-step operation. Data are presented to show the rate of exchange between tritium and hydrogen that can be expected for a variety of compounds common to a full-boiling-range gasoline. These values should be useful to other investigators using tracer programs involving tritium labeled compounds.

Jan 1, 1961

By Medardo Echegaray

Desde el punto de vista de análisis químico se buscaba estudiar un método de determinación de fierro que ofreciese una buena precisión en una zona de concentraciones. En ese sentido, el presente texto señala la determinación colorimétrica del fierro a través del método de complejo aceto-férrico. No existe intlerferencia por el manganeso, fluor o níquel. El cromo interfiere cuando se encuentra en cantidades mayores a su máxima concentración permisible o sea 0.1 mg .

Mar 1, 1963

By Y. S. Li

The life cycle assessment method is applied to investigate the environmental impacts of cop-per-slag and copper-ore concentration process. Some environmental load data of copper production are obtained. The result indicates that damage level of human health, ecosystem quality and re-sources respectively is 0.174, 0.0203, 0.246 in the copper-slag concentration and 0.112, 0.0136, 0.299 in the copper-ore concentration. Environmental impact of copper-slag production (0.44) is more than that of copper-ore production (0.42), but can meet the environmental protect demand. With domestic copper concentrate supply gap enlarging, recovering copper from slag will lead to a significant improving of resource utilization and development of circulation economics.

Jan 1, 2014

By Scott Hean

"Environment and the economy are interwoven irrevocably. They need to be publicly discussed, and discussed often so that new approaches can be understood and developed - approaches which are complimentary, not confrontational.Discussion on the environment is timely, from the perspective of mining engineers and developers, from that of bankers and from their shared perspective as people concerned with enhancing the quality of life, the environment and the economy.This paper will touch on how what is called the ""environmental economy "" that has evolved has become entangled with regulatory and financial issues in a way that is dangerous for all of us. It will also look at some of the promising possibilities that a world-wide and continuing concern for the environment holds out for us.For many decades, British Columbia has provided some of the key examples of the intertwining of environmental and economic issues, and, very importantly, providing the people prepared to do something about them.Canada's first environment minister, the late Jack Davis, came from British Columbia. He led this country's delegation to the Stockholm Environment Conference in 1972, a conference that laid the groundwork of principles necessary to establish some international certainty as to the legal liability for causing trans-national environmental damage.Another British Columbian who was also a national environment minister, John Fraser - now the Speaker of the House of Commons - was one of the first to dramatize the importance of acid rain and force it into the international public arena.Some 20 years ago, British Columbians made Vancouver and their province one of the major centres of opposition to the Alaska Pipeline and Tanker System - with some justification, it now seems.That a British Columbian , then MP David Anderson, was given legal recognition to sue in a United States' court against a system that was either in U.S. territory or international waters was an important precedent in, and of, itself in terms of environmental law. That old controversy is now a very current case study - in terms of dealing with the question of liability.-"

Jan 1, 1991

By L. C. IlsLey

Through the cooperation of the Pennsylvania Department of Mines the writer obtained from State, records detailed information concerning coal-mine accidents occurring in Pennsylvania bituminous mines during 1939, particularly those nonfatal accidents in which the injured person lost 60 or more days? time from mark. The writer wishes to acknowledge assistance received from Pennsylvania State officials, especially Richard Maize, secretary of mines, and. Joseph J, Walsh, deputy secretary of mines; also to Thomas Dickinson,3/ of the Bureau of Mines, who rendered valuable assistance in assembling the data an the several tables.

Jan 1, 1941

By M. Westerstrand

It is known that the water chemistry of the process water during ore refinement can affect product quality, such as iron pellet strength. The main objective of this study was to quantify the amounts of major elements, such as Ca, Mg, Na, S and Cl carried by process water and by magnetite grain surfaces to the end product, iron ore pellets made from magnetite ore from the Kiirunavaara Mine in northern Sweden. In addition, the amount of colloids (0.22µm ? 1kD) in the process water was examined by ultrafiltration. The amounts of various elements sorbed to the magnetite surfaces were estimated by leaching with Milli-Q water, MgCl2, NH4-acetate and Na-acetate. Total dissolved solids were between 1,446 and 1,775 mg/l, dominated by Ca, S, Na and Cl (89%). The colloidal fraction was less than 3% for major ions. For Ca and Mg, sorption to magnetite surfaces was a much more important transport mechanism for the pelletizing process than evaporated process water, but for Na, Cl and S process water was an important carrier.

Jan 1, 2010