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By B. J. CROSS., Henry Kreisinger, John Blizard, C. E. Augustine

This bulletin presents the results of 36 tests made on a 468-horsepower Edge Moor boiler fired with pulverized coal at the Oneida Street Station of the Milwaukee Electric Railway & Light Co., Milwaukee, Wis. The tests were made by the fuel section of the United States Bureau of Mines in cooperation with the research department of the Combustion Engineering Corporation. Illinois coal was used as fuel; the furnace, burners, and feeders were designed by the Locomotive Pulverized Fuel Co. The object of the tests was to determine what over-all boiler efficiency could he obtained with pulverized coal under various conditions of furnace operation and with coal of different fineness and moisture content. The investigation was thorough. The pulverized coal, as it was supplied to the furnace, was weighed in specially designed tanks placed on platform scales. Twenty-nine of the tests were of 24 hours duration, three of 16 to 18 hours, and four of 12 hours. All tests are reported excepting two-8 and 20-which had to be stopped abruptly, No.8 because a motor actuating the coal-feed screw burned out and No. 20 because of trouble with the feed pump. Tests 1 to 27, inclusive, were made with round burners and tests 28 to 3Rwith spreading burners. In the first nine tests a large excess of air was supplied in an effort to prevent the ash fusing at the bottom of the furnace. In tests 10 to 16 the supply of excess air was reduced in order to get a high efficiency, regardless of the slagging of ash at the furnace bottom. Tests 17 to 27 were made with a water screen about 10 inches above the bottom of the furnace, to make possible the burning of coal with a small supply of excess air without the ash fusing at the bottom of the furnace. Tests 28,29, and 30 were made without the water screen and with a small supply of excess air, and tests 31 to 38 with a water screen around the walls near the bottom of the furnace. Tests 32, 33, 34, and 35 were run with coarser coal than that used ordinarily at the plant. Tests 36,37, and 38 were made with undried coal.

Jan 1, 1923

By Matthew Clay, Colin Chambers, Susan Hookham

Opencast (quarries) and underground mines around the world use blasting methods to mine valuable ore. Traditional blasting systems use technologies such as electric delay detonator systems (developed in the 1950s) and non-electric detonator systems (developed in the 1970s) to initiate a detonation train to blast rock more effectively, and so retrieve valuable product more efficiently. However, the lack of precise control over blast timings with these approaches can result in undesirable outcomes such as significant flyrock, excessive ground vibration, uneven grade of rock and misfires (in which sections of the blast can remain unfired). The development of Electronic Initiation Systems (EIS), first used in the 1990s, introduced a higher level of control over the blast. These systems greatly reduce the negative issues associated with blasting. However, this precision introduces complexity, and with this complexity comes difficulty in demonstrating the predictability, safety and reliability of such systems.

Jan 1, 2017

By K. H. J. Clarke

SINCE the beginning of this century the non-ferrous mineral industry has contributed $17,809,-000,000 to the economic growth of Canada. To contemplate the vast amount of investment capital required and the resultant beneficial distribution of these billions of dollars for labour, transportation, supplies, taxes and dividends, challenges the imagination. It is the purpose of this paper, (a) to trace the development of the industry since its formative period to the present; (b) to discuss the current situation and problems; and ( c) to attempt to peer into the hazy future. Although there are 21 metals currently being produced in Canada which are classified as non-ferrous, or as alloying metals, copper, lead, zinc, nickel-the metals which will be discussed in this paper-constitute almost 60 per cent of their total value. ;The story

Jan 1, 1961

By T. A. Rickard

Flaubert, as we know, laid stress on the selection of the right word, le mot juste, the precise epithet, the word that belongs to the thing. A sentence, or even a paragraph, may be spoiled by the use of a word that is not proper, that does not fit or is foreign to the meaning intended. An Australian mining expert is reported to have said: You have a property of considerable value, and what I saw warrants a good development of very rich cubicular galena, with gossan intermixed. 'Cubicular' means `belonging to a small bedroom', a `cubicle' being a sleeping compartment. He meant `cubic', of course. This is a malapropism, and reminds me of the lady from Chicago that, on her return from Europe, said how much she had enjoyed the rural parts of France, because, among other things, it was "so delightful to hear the French pheasants singing the mayonnaise to the tune of the Los Angelus". It is impossible to amalgamate coal-tar thoroughly with the pulp in the agitating-tank. In metallurgy, `amalgamate' refers to the combination of mercury with one or both of the precious metals, forming an amalgam, which is an alloy of mercury with another metal. It differs from other alloys, such as brass or bronze, in being made without the aid of heat, inasmuch as mercury is molten at the ordinary temperature. The word comes to us from the Greek. through Old French and means `something soft'. It is a mistake to use technical terms, having a specific meaning, for purposes that are foreign to that meaning. The writer of the quotation is not discussing any combination of metals; he is dealing with the physical process of mixing and is using 'amal-

Jan 1, 1931

Young professionals are riding the current wave of high demand for their services and relatively little competition for placements. The attraction and retention of quality incumbents has therefore become a significant strategic issue for companies in our industry. Money is important, but poorly structured career development and lack of learning opportunities can discourage the highest paid professionals from being enthusiastic and striving for excellence. This will inevitably lead to the search for a new position. Important factors at play include the young professionalÆs lack of understanding of career pathways and poor quality, or lack of, structured on-the-job training and professional development. Too often young and not so young professionals are faced with the reality that fabulous looking (and paying) jobs can be quickly reduced to the monotony of repetitive tasks in an isolating environment. While it is the responsibility of the incumbent to manage their own career and professional development, without experience, how is anyone meant to understand the importance of their roles and the options for career development? Mentoring is therefore essential to the strategic plans of every organisation and the strategic plans of every professional. Mentors will accelerate learning, guide decision making and develop both competency and confidence as they share their experience, both technical and regarding the machinations of a particular discipline, within our industry. Mentors need not be from the same organisation as the mentee and in some cases this may be a distinct advantage. This paper discusses mentoring as an opportunity for young professionals and mentors to initiate and maintain a supportive relationship, the responsibility of management to get mentoring right and the responsibility of young professionals to demand the opportunity for professional development through mentoring.

Jan 1, 2006

By E Claridge

There are a number of major infrastructure tunnelling projects currently underway or proposed in New Zealand, including construction of new road and rail facilities and the refurbishment of existing road tunnels. These new projects have triggered a rethink of traditional practices in underground fire and life safety and local regulation.While there is a current surge in activity, tunnels have been a signifi cant part of New Zealand’s transport infrastructure for over a century. Despite this background, the new projects commonly face challenges that are symptoms of a national regulatory environment that has aspects that are inappropriate for underground environments. There are inconsistencies in local regional regulation and an absence of national guidance and standards relating to tunnel design. Historically, New Zealand has looked across the Tasman for guidance. Although recent overseas tunnel designs present learning opportunities, the adoption of international best practice and standards may not necessarily address local expectations or needs.This paper explores a number of specific matters affecting the design of road and rail tunnels in the New Zealand context, namely; the Building Regulations and associated local consenting processes and parties, and the responsibilities and needs of the New Zealand Fire Service.The discussion highlights the importance of a collaborative approach involving the designer, asset owner, regulators, emergency services, and other parties, and ensuring up-front clarity in design responsibility and ownership of residual risk.

Mar 8, 2011

By Joseph A. DeCarlo

According to the annual survey of beehive-coke plants by the Bureau of Mines, United States Department of the Interior, there were 61 plants with 9,549 ovens in the United States on December 31, 1956, This publication in¬cludes only those for which an annual report was filed with the Bureau of Mines. Not all plants listed were active, however, as nearly one-third of those canvassed were idle all year. A compilation of the returns showed that 44 plants with 6,920 ovens were active part or all year and 17 plants with 2,629 ovens were idle throughout the year. The capacity of beehive ovens has fluctuated between 6 and 14 million tons during the past decade. At the end of 1956, the annual coke capacity of beehive ovens on which reports were received amounted to 5.8 million tons. As noted in table 2, however, not all of this capacity was in operating condition, as 2,093 ovens with a capacity of 1.2 million tons were not operable on [ember] 31, 1956.

Jan 1, 1958

By Rodney Hundermark

At Anglo American Platinum’s Polokwane Smelter, radar instruments are being used to provide continuous measurement of the concentrate feed level in the six-in-line electric furnace used for smelting of nickel-copper concentrates containing platinum group metals (PGMs). The radar instruments are installed directly on the furnace roof, and a mechanical system has been designed to protect them from radiation and elevated freeboard temperatures and pressures. Signal validation criteria have been implemented to ensure that proper level measurements are being used by the PLC system. The feedback from the radars has provided an improved understanding of the furnace behaviour with respect to concentrate feed level control, individual feeding events, global feed rates, feed distribution and bath disturbances. In combination with a dynamic mass balance for continuous calculation of liquid level in the furnace, the radar measurements have enabled more precise feedback control of the concentrate blacktop depth. In turn this has yielded improvements in furnace stability.

By Yoshihiko Maeda

It is said that the 21 st century will be an era of the remedy of the global environment. In order to reserve natural resources for the future and to avoid the dispersion of heavy metals after usage and to avoid pollution problems, it is extremely important to recycle heavy metals as much as possible by reasonable recovery procedures. The nonferrous metal industry is expected to play a important role in the recycling of heavy metals that are originally their products. From the depressed metal price experienced in Japan in 1980th due to the sudden change in current exchange rate between US dollar and Japanese yen, one of major nonferrous metal company, Dowa Mining, has diversified its business area not only to the so-called down stream, but also to the environmental business including metal recycling, industrial waste treatment and soil remediation by utilizing technologies and facilities once used or still used for mining and smelting of copper, zinc, lead and precious metals. In this paper some of these applications will be presented.

Jan 1, 2003

By G. Laird, N. B. Gray, N. Lawson

"Photographic, video, laser, hot film and conductivity methods are used in the experimental study of gas-liquid flows. A discussion of their capabilities and limitations are given in this paper illustrating the wide range of phenomena that can be studied. Most of these methods are limited to physical models at room temperature with transparent fluids, although they can be extended for use with opaque and hot fluids. A number of these techniques have been used by the GKW CRC in studies on industrial plants and their usage is increasing although a number of technical difficulties still need to be overcome. An in-depth discussion of the laser doppler anemometry (LDA) and particle image velocimetry (PIV) methods is given with experimental results on the flow field of an air plume in water based on advanced development of the techniques and studies carried out at the GKW CRC. The LDA method provides high resolution data on the velocity profiles, while the PIV method provides an overall view of the complex flow structure occurring at the gas-liquid regions. These two methods complement each other in providing experimental data for validating numerical models and exploring the complexities of multi phase flows.IntroductionThe injection of gases into melts is an important operation in the metallurgical industry. It is used in converters, anode furnaces, blast furnaces, ladles, bath smelters, zinc fumers and many other smelting processes. In many of these processes, the gas is injected into a molten bath resulting in the formation of bubbles that promote reaction, mixing, alloying and heat transfer. The study of gas-liquid systems presents enormous challenges to the researcher due to the complexity of the mathematical and physical modelling which require innovative numerical and experimental skills."

Jan 1, 1996

By T Vijayakumar, Vipul Dobhada, Rajesh Patel, Swarnadip Dey, Naveen Babu D

The most challenging scope of any bridge project in marine or inter tidal zone is to construct sub structure like well Foundation, group pile, pile cap etc. Similarly, it also affects the marine environment/ecology to a great extent. Understanding the level of difficulties and aiding to provide an environment friendly solution, various options are analysed to overcome these and found mono pile to be the best alternative in this context. Generally, the foundation type of any bridge constructed in river, marine or intertidal zone in India is preferred for group piles. For the first time, monopile is being accepted as the foundation of bridge in India at Mumbai Coastal Road Project. The diameters of the monopiles used in this project are 2.5 m and 3.2 m. Hence, the challenges involved in monopile construction and experiences to overcome it are worth to share. Here, a brief discussion on environmental, geological issues and the needs of monopile as the foundation of bridge has been discussed. Furthermore, the monopile construction stages and confirmation of monopile capacity through different load tests have been elaborated.

Sep 1, 2022

By Donald A. Bruce

"The Deep Mixing Methods (DMM), in their current forms, have been employed in the United States since 1986, although an earlier version had seen service from 1954. The earlier developments were strongly influenced by practices in the Nordic countries and Japan, while by the late 1980’s several DMM systems had been developed in the U.S. itself. Since then, DMM has continued its evolution, principally via the challenges of a series of large, landmark projects, but also via distinct, significant technological advances. This paper highlights the key points in the history of DMM in the U.S., and provides an overview of the different methods currently in use.IN THE BEGINNINGIt is a common misconception that the history of applications of the Deep Mixing Methods (DMM) in the United States dates from 1986 when SMW Seiko Inc. — a subsidiary of Japan’s Seiko Kogyo Company — was established in the Bay Area. However, the author believes that Intrusion Prepakt Co.’s patented MIP (Mixed in Place) system had been used, albeit sporadically (about 30 projects are recorded), since 1954 (FHWA 2000, 2001). Ironically, by 1961 this single auger method had been extensively used under license in Japan for excavation support and groundwater control — by the Seiko Kogyo Company. By 1972, the original MIP technique had been succeeded by more advanced Japanese methods, involving multiple augers. Intrusion Prepakt have long since become defunct.The first systematic studies of contemporary Deep Mixing Methods in Japan began in 1967 when the Port and Harbor Research Institute of the Ministry of Transportation began laboratory testing using granular and powdered lime for treating soft marine soils. Fundamental studies continued through the early 1970’s, by which time the development of industrial scale equipment was well advanced, having its first application on a marine trial near Haneda Airport. Coincidentally, laboratory and field research also began in 1967 in Sweden (“Swedish Lime Column Method”) for treating soft clays using unslaked lime. Reportedly the progenitor was a Norwegian, Kjeld Paus, who had made observations on fluid lime columns in the U.S. It would seem that developments in Japan and the Nordic countries proceeded independently until 1975 when the technology leaders from each group (Broms and Boman; and Okumura and Terashi, respectively) presented their — very similar — findings at a conference in Bangalore, India. Limited technical exchanges ensued thereafter.Whereas the Nordic developments continued to focus on the use of dry reagents (cement and lime) and relatively light equipment compatible with operating on and in very soft clays and organics, the Japanese progressed into the use of fluid reagents (cement-based grouts) and heavier equipment for both marine and land-based projects. Thus, by 1986, there were a large number of proprietary (wet and dry) DMM systems in Japan, and a rapidly growing market already by then accounting for over 12,000,000 m3 of ground treatment."

Jan 1, 2015

By E. J. Gleim

The Bureau of Mines customarily publishes lists of equipment meeting its safety standards to keep the mining industry informed as to the development and availability of mining equipment that can be used safely. The present list supplements Bulletin 543, Permissible Mine Equipment Approved to January 1, 1953, as well as Information Circular 7722, Permissible Mine Equipment Approved During the Calendar Years 1953-54. Because standards have been revised and new ones added by the Bureau, this list contains classes of equipment not previously covered.

Jan 1, 1958

By M. W. Lightner

IN 1947 the steel industry rebounded from its wartime effort and produced a record-breaking peacetime tonnage of steel ingots. During the first six months of the year the industry produced 42,000,000 tons of ingots and expected to produce 85,000,000 tons for the year. With a rated capacity of some 91,000,000 tons, production was at a rate of about 93 per cent of capacity. Credit must be extended to the steel producers who have maintained this steady state of operations while faced with many problems, not the least of which was a continued shortage of satisfactory scrap. Furthermore, the steel industry started a record-breaking peacetime expansion program at a total cost of more than $1,000,000,000. This program will increase the ingot-making capacity of the country by 2,500,000 tons and should be completed in 1948.

Jan 1, 1948

By S. Malinov, J. J. McKeown, W. Sha, S. McShane

"A model is developed for prediction of fatigue stress life S-N diagrams for Ti-6Al-4V alloy at different conditions, using Artificial Neural Network (ANN). Different factors which have influence on the S-N diagram are involved as input parameters of the NN, namely microstructure, environment, texture, test/work temperature, surface treatment and stress amplitude. As the output the S-N fatigue diagram is simulated and plotted.The model is based on standard multilayer feedforward neural network. The NN is trained with a comprehensive data set collected from the literature, using Levenberg-Marquardt training algorithm in combination with Bayesian regularisation. A very good performance of the trained Neural Network is achieved. Good correspondence between ANN"" prediction and experimental S-N diagrams is observed. Using the model S-N diagrams for different conditions are predicted and analysed. Graphical User Interface is developed for use of the model. We believe that the model will be important for practical applications in solving various problems on fatigue behaviour of the titanium alloy.IntroductionTitanium and its alloys have an increasing range of applications due to their very good combination of mechanical properties, corrosion and erosion resistance. They are currently finding widespread applications in many industries due to their desirable and versatile properties. Most important among the alloys is Ti-6AI-4Y. Jet aircraft manufacturers are the principal 'consumers of Ti-6Al-4V and it is often specified for critical parts, the failure of which could result in the loss of an entire system. A generic class of Ti-6AI-4V has been developed over the past years and it has become the best understood of all the titanium alloys. The advantages of titanium alloys include: (i) low densities, giving very attractive strength to weight ratios allowing lighter and stronger structures; (ii) superior corrosion and erosion resistance in many environments; (iii) high temperature capability. Although the titanium materials are still considered as expensive materials, for many applications the cost of titanium alloys can be justified on the basis of their desirable properties."

Jan 1, 2001

By F. E. Joyce, Charles Prasky

This report describes the response to high- temperature sulfatization of a variety of manganese minerals and companion compounds which may occur either as a principal component or as a gangue material in low- grade manganese deposits . Fourteen manganese samples representing oxide , carbonate , and silicate minerals as well as seven compounds which might occur as gangue with manganese minerals were tested batchwise in a bench- scale apparatus under conditions which would be favorable for the sulfatization of manganese . The manganese minerals substantiated thermodynamic predictions and responded to sulfatization but to varying degrees . The gangue materials , MgO , MgCO,, CaO , and CaCO3 , were sulfatized readily in contrast to the iron oxides and the aluminacontaining material which were not .

Jan 1, 1964

By Dupuy. Leon W.

"INTRODUCTION For many generations the Indian tribes of the southwestern deserts knew of the thermal springs of the Coso District in southwestern Inyo County, Calif. Belief in the reputedly healing qualities of the waters and muds of the area was widespread. F. J. Sanders discovered mercury in the siliceous sinter around the hot springs while he was exploiting the district as a health resort. In searching for new domestic sources of supply of strategic minerals, authorized under the Strategic Materials Act, 3/,the Geological Survey 4/ first examined the deposits, which were drilled and sampled by the Bureau of Mines in the spring of 1941.The deposits investigated comprised three units known, respectively, as The Devils Kitchen, Nicol, and Wheeler. Most of the work was done at the first two.Of particular interest in the Bureau's work on the project was the adaptation and use of the bucket drill as a tool for sampling shallow, soft ore deposit."

Mar 1, 1948

EdgaR S. Cook, Pottstown, Pa.:—Many friends and acquaintances seem to be under the impression that the Warwick Iron & Steel Co. received a' license from Mr. Gayley, free of cost, as an inducement to adopt the process. This impression is not correct, since the license was paid for, and I think it was the first payment that Mr. Gayley received for the use of his process. As president of the Warwick Iron & Steel Co., I am responsible for its earnings, and with only the experience at the Isabella furnaces as a guide, the directors of the company considered that there was a great risk in expending the large sum of money required for the plant. They, however, acted favorably upon my recommendation, and to this extent I am responsible for the installation at the Warwick furnaces. I made the best agreement possible with Mr. Gayley, and naturally our company received certain advantages. It will be contrary to all experience if subsequent plants do not show some improvements and economies in construction. It is to our indirect benefit that all subsequent licenses granted by Mr. Gayley should be charged at a much higher rate than we paid; and I trust that he will see to it that all such licenses granted, especially to companies making merchant iron, shall be at a maximum figure. The Warwick Iron & Steel Go. is not interested in any way in exploiting the merits of the Gayley dry-blast process; on the contrary, looking at the subject from a narrow and selfish standpoint, it is to the advantage of our company that no merchant blast-furnace competing with our iron-product should be equipped with a dry-blast plant. There is a clause in the contract with Mr. Gayley, whereby our company agrees to furnish him with all the data derived from the operation of the dry-blast plant, and that he or his

Jan 1, 1909

By Jr. Gabler

World resources of platinum-group metals appear ample for the foreseeable future; however, political and economic events in the last two decades have caused concern over the availability and reliability of an uninterrupted supply. Because of this concern, the U.S. Congress requested that the U.S. Bureau of Mines initiate a study of the flow of platinum-group metals in the economy that would delineate and quantify the production areas in which metal values are lost. As a result, the Bureau has developed a computerized commodity flow model for strategic and critical materials. Major attributes of this flow model are as follows: (1) it is generic and applicable to most commodities and (2) it can be updated as supply, demand, and/or production data change. The original model developed for cobalt, with slight modifications, was used to track the flow of platinum-group metals. This report follows the flow of platinum-group metals through their metallurgical, catalytic, and chemical applications and highlights areas in which significant losses occur because of downgrading, export, or disposal. The study indicates that materials containing about 63,426 kg of platinum-group metals were lost or could not be traced in 1989, representing about 63 pct of U.S. domestic consumption.

Jan 1, 1991

By Lukas Walder, Roland Arnold, Raphael Zuber, Richard Gradnik

This paper presents the construction of the ventilation shaft for the single-tube, doublelane Kramer tunnel. The project is located in the Federal State of Bavaria, Germany. This road tunnel, which has been under construction since December 2019, is the key component of the western bypass of the town of Garmisch-Partenkirchen. Once completed, it will relieve the town’s central district from enormous volumes of traffic. The contractor is the joint venture named ARGE Kramertunnel consisting of BeMo Tunnelling and Subterra. The whole project will be completed and handed over to the project owner, Staatliches Bauamt Weilheim, in 2023. The opening of the entire bypass section including the tunnel to traffic is planned for 2024. The tunnel, with a total length of 3,609 m (2.24 miles) and an estimated cost of EUR 178 million incl. VAT (US-Dollar 201 million), is designed as a single-tube, double-lane structure with one traffic lane for each direction of travel. The safety issue that exists for singletube tunnels is solved by a parallel escape tunnel passable for vehicles. For tunnel ventilation, an intermediate shaft has been designed with a depth of approximately 90 m (295 feet) and an inner diameter of 4.5 m (14.8 feet). All tunnels and ducts are excavated according to the principles of the New Austrian Tunnelling Method (NATM). The geological and hydrogeological conditions, the change in the profile (from round to square geometry), and also the shaft being located at a high elevation presented a demanding technical and logistical challenge. The site arrangement with the pit bank was located in a cut, the slopes of which had to be stabilized with shotcrete and soil nails. This excavation was carried out from the fall of 2020 to the beginning of 2021 because construction operations had to be completed outside the nesting period of protected birds.

Jun 13, 2023