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By CLARENCE WM. POY

THE most common difficulty faced by an engineer or mine operator when opening a new property in a new field is the lack of roads and of cheap transportation. This one item often swings the balance of success or failure in starting a project. In Alaska, as elsewhere, such problems are more or less serious. In the boom days around the Valdez district, as well as in other parts of this territory, freighting was accom¬plished by dog teams or horses, or even by men that were willing to put their shoulders into harness, because there were virtually no roads. More important, there was only one time when supplies could be transported, and that was when there was suffi¬cient snow on the ground following a heavy wind. Then, and only then, could one depend on the snow to support horses and sleighs, and be sure that the gulleys, streams, and crevices in the glaciers were filled with snow to avoid pitfalls. These methods were used when one had no roads, no streams in the summer to float a barge, or even a trail for a pack train. If the snow was deep and soft, trans

Jan 1, 1935

By M. L. Wang, S. R. Short, E. M. Daniloff, E. L. Petsonk, D. M. Mannino, G .. R. Wagner

"Background—It has been suggested that health related job selection is a major cause of the healthy worker effect, and may result in inaccurate estimates of health risks of exposures in the working environment. Improved understanding of self selection, including the role of airway hyperresponsiveness, should improve accuracy in estimating occupational risks.Methods—We evaluated symptoms of the respiratory tract, lung function, occupa¬tional and smoking histories, and airway responsiveness from a cross sectional sur¬vey of 478 underground bituminous coal miners and non-mining controls. Workers with abnormal spirometry were excluded from methacholine testing.Results—Methacholine responsiveness (= 15% decline in forced expiratory volume in one second) was associated in both miners and controls with reduced ventilatory lung function and an increased risk of respiratory symptoms. Miners with the longest duration of work at the coal face had a low prevalence of methacholine responsiveness, compared with miners who had never worked at the coal face (12% v 39%, P < 0.01). Throughout their mining careers, miners who responded to methacholine were consistently less likely to have worked in dusty jobs than miners who did not respond to methacholine.Conclusions—These results provide evidence that workers who are employed in dusty jobs are less likely than their unexposed coworkers to show increased non-specific airway responsiveness, pre-sumably as a result of health related job selection. Surveys of workers in which responsiveness data are unavailable may underestimate the effects of dust exposure on respiratory health."

Dec 1, 1996

By R. Viljoen, K. Manns

"The mining industry instinctively follows rule-of-thumb design velocities often based on very simplistic theoretical “economic velocity” optimization calculations to determine airway sizes. Although these are important building blocks in ventilation planning it should be recognized that mines are far more complex and various, often opposing factors, are at play. Therefore, it is important that each ventilation situation be analyzed on a case-by-case basis to determine the best-fit solution for an operation. The ventilation design process should not necessarily be constrained by theoretical optimal economic velocities that become rules-of-thumb. In some cases, this could lead to unrealistic infrastructure requirements and exorbitant capital expenditure. This type of design often lacks corporate support leading to a scenario where no ventilation upgrades are implemented. Economic velocities typically consider the cost of power, development costs and operational risk. These typical rules-of-thumb work reasonably well as a starting off point when considering feasibility of greenfield projects. For established mines that are looking at expansion these rules may not be appropriate due to capital expenditure constraints or geotechnical ground conditions. The theoretical optimum should be reviewed in the case of an established mine where existing infrastructure could perhaps be maximized. For example, the geotechnical risk of large diameter raises at depth may require multiple small diameter raise to maintain the theoretical economic velocity. If a mine has a life of less than 5 years, then the cost of power is an insignificant proportion of the total owning cost. For these mines, operating the ventilation raises at an increased velocity to avoid a complicated and expensive capital upgrade might be the more appropriate option, even though it opposes the traditional rules-of-thumb. Mines which are capital constrained may be better off accepting a higher operating cost for the interim or settle for minor infrastructure upgrades rather than run the risk of the entire ventilation upgrade not being approved at all. This paper explores a number of examples derived from case studies undertaken by the authors for several deep mechanized mining projects in Australasia. The examples explore conditions under which higher than the economic norm would be applicable."

Jan 1, 2019

By Antonio Adel dos Santos

Em agosto/2014 foi introduzido o gás natural, GN, na matriz de combustíveis dos fornos de reaquecimento de placas da Linha de Tiras a Quente, em Ipatinga, eliminando o óleo combustível deste processo. Isto demandou o ajuste dos parâmetros do modelo matemático de controle automático do reaquecimento, que estava ajustado para a queima de mistura de gases siderúrgicos e óleo combustível. O ajuste foi realizado com base em resultados de experiências de medição das curvas de aquecimento com placas especialmente instrumentadas. Verificou-se que os gases da combustão na presença do GN ficam mais quentes na região do início do forno, próximo do canal de fumaça, elevando com isso o perfil térmico do forno. Em consequência, as temperaturas de desenfornamento da placa ficam mais elevadas em relação ao aquecimento na ausência do GN, comparando-se condições de processo e de material similares. Os ajustes do modelo foram implantados dentro do escopo de uma melhoria geral introduzida no sistema de controle automático dos Fornos, permitindo a determinação correta da temperatura de desenfornamento e a operação otimizada dos fornos do ponto de vista de aquecimento da placa.

Aug 16, 2017

By Leonardo Zuchi Guio

A ArcelorMittal Tubarão vem trabalhando continuamente no aumento de produção de seu Laminador de Tiras a Quente (LTQ). Com o aumento da produção, o risco de colisão de material ao longo do LTQ, com maior possibilidade de ocorrência na mesa de resfriamento de tiras, se elevou. De forma a permitir aumento de produção e evitar colisão de material, desde o início de 2016 iniciou-se um trabalho de ajuste no modelo. Dado que o modelo consiste na determinação do ritmo de laminação a partir da liberação de extração de placas dos fornos, início do processo de laminação, o trabalho envolveu a criação de um ponto de controle de ritmo no meio da linha do laminador. Para suportar um controle adequado nesse ponto, foram necessários ajustes de parâmetros e cálculos para aumento da precisão do modelo. Esse trabalho apresenta os ajustes realizados para utilização do novo ponto de controle, bem como os ajustes realizados para aumento da precisão do modelo e os ganhos de produtividade obtidos a partir desses ajustes.

Oct 30, 2017

By Eifu Moriyama

In 1953, Akita Plant, having a capacity of 560 tons per month, was built at Akita city by Mitsubishi Metal Mining Co., Ltd. for the purpose of treatment of the Ikuno and Akenobe Mines&apos;s zinc concentrates. Akita city, in whose neighborhood the black ore has been discovered, is located about 500 Km north of Tokyo and faced with the Japan Sea. This plant has been continuously expanded to have the capacity of 7,500 tons per month by the end of 1969. Efforts have been made to mechanize installations and to achieve continuous process. One of the characteristics of Akita Plant is the recent establishment of the residue treatment process. Many processes had been investigated, and finally commercial sulphate roasting of the residue has been carried out since 1965. At Akita Plant, special high grade electrolytic zinc, zinc alloy for die-casting (MAK brand), cadmium, cement copper and sulphur dioxide gas are produced. Sulphur dioxide gas is sent to the next door fertilizer plant to make acid. Table 1 shows production and the average assay of the electrolytic zinc and cadmium in 1969. This plant is divided into four main sections, two subsections, and residue treatment sections: Main sections are: (M-1) roasting section, (M-2) leaching and purification section, (M-3) electrolysis section, (M-4) melting and casting section,

Jan 1, 1970

By R. Dewey

WHAT IS AI? It&apos;s very hard to say. Most researchers and practitioners disagree with nearly any attempted definition, but most would agree that A1 does deal with the development of computer-related methods o f problem-solving. Artificial intelligence is a discipline which seeks to emulate human anatomy and/or thought processes by applying computer science, electronics, and mechanical engineering to the development of natural language processing, machine vision, robotics, and knowledge-based expert systems. Integration of these four fields will someday produce the robots of today&apos;s science fiction. A1 addresses problems of structuring large amounts of knowledge and representing relationships with rules and semantic frameworks rather than with mathematical equations. A1 is convergent rather than divergent - - conventional conputer applications use relatively small quantities of input to generate large output, but A1 generally reduces large amounts of information to establish a few major conclusions. The development of A1 has prompted greatly increased efforts on the part of scientists and engineers to understand just how humans think, organize information, approach problem-solving, and form conclusions. Some of the more exciting and possibly far-reaching advances in A1 are coming in this more-or-less soft-science area. Thirty years of A1 research (dating from a 1956 conference at Dartmouth College at which the term A1 was coined) has already spawned many widespread, almost ordinary, products: window graphics, hand-held controllers (mouse). function menus, etc., all in an attempt to make computers and people more compatible. WHAT IS AN ES? A1 can be used to develop EXPERT SYSTEMS, which are computer programs or systems which contain knowledge and rules by which problems can be solved. or at least by which possible solutions can be suggested for very complex problems. A1 can be used to better define problems so that solutions can be found. An ES is designed not to process numbers, but to process information according to rules and logic derived from actual practice and experience. WHY AI? WHY ES? Companies are increasingly aware of the value of accumulated knowledge and experience in designing, building, operating, and maintaining the increasingly complex or expensive physical plants in any business. As knowledge branches out and becomes more specialized, the accumulated learning of a veteran operator or manager or engineer becomes a scarce resource well worth preserving. EXPERT SYSTEMS offer a means of doing that, reinforcing, not replacing, human capabilities.

Jan 1, 1987

By Guan-Yong SHI, Cong Wang, Zhi-he DOU, Ting-an ZHANG, Shi-gang FAN

Based on the pre-works, this paper proposed a new short stage process of the intensify aluminothermy reduction by the stage to prepare high titanium ferroalloy with low O and Al contents. We investigated the effects of Al and Ca and Si combination reduction agent, slag type and step-up reduction conditions on the Al content and distribution in the alloy. The results show that the step-up reduction can not only reduce effectively the oxygen content in the alloy, but also reduce effectively Al content. For instance, the oxygen content in high titanium ferroalloy is within 1%~4%, and the Al content is within 1%~5%. Its quality reaches the requirement of high titanium ferroalloy prepared by remelting process.

Jan 1, 2015

By F. Filzwieser, K. Gamweger

The process of gas purging in molten aluminium has been an industrial practice in Europe for many years. The advantages are a reduction in the hydrogen content and impurities in the melt, as well as a homogenisation of the temperature and chemical analysis in the molten metal. Formerly used lances or impellers are being replaced by porous plugs which are installed at the bottom of the furnace. This special product of RHI Refractories has proven its efficiency in primary melting as well as in die cast, sheet and extrusion plants.

Jan 1, 2004

By Yessica Idrogo

"Undoubtedly mining is currently the activity that brings a great development for all countries involvedin this industry, which means that to develop mining requires adequate explosive mixtures. The following work about AL/AN/FO is presented, knowing that this is a dry blasting agent, which iscomposed by ammonium nitrate, petroleum diesel N°2 and aluminum (AN, FO, AL). It is known that this dry blasting agent AL/AN/FO was invented by A. Baver Ph. D. in Marcona Mining Company, 12/12/1968, where in that investigation also worked Carlos Agreda Ph.D. as assistant of the mentioned inventor."

Jan 1, 2017

By Milton Fies

ALTHOUGH pig iron from iron ore and red cedar charcoal preceded the mining of coal by many years, for tradition says that Alabama iron was used to shoe the horses of Andrew Jackson&apos;s soldiers, coal was not produced until 1830. In that year, coal was mined in Tuscaloosa County, in the vicinity of what is now the University of Alabama, and shipped on flat boats (obviously during the wet season, for there were many shoals) down the Warrior River to Mobile. About that time, the first railroad, the Decatur & Tecumseh, was being constructed in northern Alabama to overcome the obstructions to freight traffic caused by the now well-known Muscle Shoals in the Tennessee River. This railroad was patterned after a railroad at Mauch Chunk, Pa., which was used for hauling anthracite from the Panther Creek valley. The Alabama railroad, which required about four years to complete, was 46 miles long and was used solely for the transportation of cotton. Although it was a failure, it demonstrated the practicability of the undertaking, and the succeeding railroads, which were begun in 1834, 1848, 1852, and 1853, added immeasurably to the development of the coal resources of the state. Between the years 1830 and 1860, practically all the coal mined in the state was dug from the outcrop near the river or from the river beds, and shipped by boat to Mobile. Transporting coal down the Warrior River was one of great risk, required much skill, and frequently had heavy losses. It is recorded that this coal was sold to the gas company in Mobile in 1844; it was most likely mined from the Black Creek Seam. In 1914, on the completion of Lock 17, the Warrior River became a navigable stream from 9 miles above Cordova, Ala., to Mobile and offers a great opportunity for the future development of the coal resources of the state.

Jan 9, 1924

By David Peterson, Terry Tucker, Rafael Serrano

"The Alameda Corridor-East (ACE) Construction Authority awarded a $172.6 million contract to Walsh Construction Company (Walsh) for the construction of a 2.2 mi (3.5 km) long grade separation including a 1.4 mi (2.3 km) long trench that will allow Union Pacific Railroad (UPRR) and Amtrak passenger trains to operate below ground through the city of San Gabriel, Calif. The project is necessary as the ACE trade corridor accommodates approximately 60% of the shipping containers that move from San Pedro Bay, the busiest port facility in the western hemisphere, to the rest of the country via an extensive rail network. Rail traffic is expected to increase by as much as 160% by 2020, and the resultant delays to vehicular traffic is projected to increase by an estimated 300%. The San Gabriel Trench Project is designed to mitigate the effects of this increased train and vehicle traffic throughout the San Gabriel Valley. Malcolm Drilling Company (Malcolm) was selected by Walsh to perform the specialty foundation and ground improvement work for the San Gabriel Trench.This project is part of ACE’s program to create 22 grade separations and safety improvements at 39 grade crossings throughout the San Gabriel Valley. In addition to safety improvements that will eliminate crossing collisions and delays to emergency responders, the project will reduce vehicle congestion and emissions from passenger cars and trucks having to wait for passing trains, and the project will also reduce locomotive horn and crossing bell noise to local residents.Construction of this portion of the project began in late 2012, and it is scheduled to be completed by the end of 2017, having created approximately 9,000 jobs during this period. The project is being funded from Proposition 1B transportation bonds approved by California in 2006, the Metropolitan Transportation Authority (MTA) Measure “R,” and other local and federal funds. The overall project cost is estimated to be $313 million."

Jan 1, 2017

Carlisle: An old friend and good friend, Alan Bateman, is the Silliman Professor of Geology Emeritus at Yale and editor of the Journal of Economic Geology. Now, Alan, let&apos;s start off by telling us something about how you became interested in copper. Bateman: Well, after I left Yale in 1913, I was appointed one of the field members of the Secondary Enrichment Investigation. We spent three years in the field studying all the copper deposits of North America, trying to find out how secondary copper enrichment took place. As part of this investigation, I went up to Kennecott, Alaska, in 1916. After the trip I was asked by the president of the company to become consulting geologist to them. I accepted his offer, and to this day I&apos;m still consulting geologist to the Kennecott Copper Corp. Up at Kennecott, there were both Henry Krumb and my good friend Henry DeWitt Smith, who was general superintendent. He and I had been together at Yale, and I had ushered at his wedding. Interestingly enough, Henry took his bride to Alaska and I took mine there two months later. My assistant was Don McLaughlin, and I think that was his first experience in a mining camp. We published a paper on Kennecott together and cemented a friendship lasting to this day.

Jan 11, 1964

By J. L. Fuentes-Cantillana, Á. Rodríguez, P. Morillo

Evacuation operations from work places in the case of an emergency are the key to minimising the effects of catastrophic type accidents such as fires, explosions, cave-ins, floods, etc. The correct planning of these operations, having the necessary means for sounding alarms and communicating and suitable training of personnel are the key factors for guaranteeing successful evacuation. The article gives an analysis of the problem in the case of subterranean mining and various types of work developed by AITEMIN in this field, including the development of new alarm and communication means specially adapted to the characteristics of mining operations, development of tools for help in the preparation of emergency plans and experiences in the education and training of personnel.

Jan 1, 2003

By H. Foster Bain

(San Francisco Meeting, October, 1911.) [SECRETARY&apos;S NOTE.-This paper, presented in oral abstract, at the San Francisco meeting, was not at first supposed by Mr. Bain to be required for publication in the Transactions; and the excursion to Japan, in which he took part, immediately after the San Francisco meeting, delayed his presentation of the manuscript. After his return to San Francisco, Mr. Bain, in view of the importance of his paper and its discussion, kindly furnished it in full. The delay in its publication (since it was received in April last) has been due, partly to the circumstance that other contributions had meanwhile acquired the "right of way," and partly to the consideration that, the situation contemplated in Mr. Bain&apos;s paper having remained practically unchanged, the paper and its discussion would not lose force or timeliness by this lapse of time.-J. S.] No acute observer of public affairs can have failed to observe a growing disposition on the part of the public to change emphasis in government from political equality to social justice. When our own government was founded it was felt to be sufficient to secure to each individual the fullest possible freedom of opportunity, and such a scheme was excellently adapted to the rapid development of a large territory having a small population. As the number of people in a given area increases, there are more points of contact and conflict; each must move in a smaller orbit, and there must be more regulation. Germany is making faster progress in industry than is any other country. The principal reason is the insistence there on team-play. In Germany there are fewer multimillionaires and more socialists (spelled with either a big or little " S ") than in any other of the leading countries; but Germany wins trade and is steadily improving the conditions of life for her citizens. To some, the change from the freest individualism is welcome; to others it is intensely unacceptable. To this fundamental difference in view-point may be imputed much of the vigor with which the controversy regarding coal-lands has been waged. That present conditions in Alaskan coal-fields are extremely unsatisfactory is generally recognized, but there are wide dif-

Aug 1, 1912

By T. Braun

In 1911, a young mining engineer named Bartlett Thane assembled a large claim block, 4 miles southeast of Juneau, Alaska. Across the Gastineau Channel on Douglas Island, the Alaska Treadwell Gold Mining Company had, by 1904, produced gold valued at more than three times the purchase price of Alaska in 1867 (Kelly, 2010). Thane knew his deposit was lower grade than other mines or prospects in the area; however, if the deposit was developed on a large-scale, the trend and size of the deposit made the project potentially economic. In 1911, Thane developed a business plan for the project and successfully attracted investor interest. In 1912, Daniel C Jackling visited the property at the request of an east coast investment group. Upon inspection of 5 years of production records for the Perseverance Mine, Jackling saw an opportunity to apply the low-grade/high volume milling technology which was widely adopted to the copper porphyry deposits of the southwestern U.S. With a design capacity of 6,000 tons per day (5,454 tonnes/day), Jackling’s innovative mill design would require high volume underground mining methods and the power of two new hydroelectric projects. By 1915, the Alaska Gastineau Mining Company was in full production. Between 1915 and 1919, the mine and mill set production records for haulage and throughput. The hydroelectric projects proved to be successful engineering marvels. Operational difficulties related to ore grade, refractory elements and labor shortages interrupted production on an increasing basis. In 1921, the mining company permanently shut down operations. INTRODUCTION The Juneau Gold Belt begins at Windham Bay near the southern end of Stephens Passage and extends approximately 100 miles north to Berners Bay (Figure 1). The first large-scale and sustained underground mine, operated by the Alaska Treadwell Gold Mining Company in the late 1880’s, established the Juneau-Douglas area as the regional hub for transportation and development. In the mid-1890’s, the combined population of Juneau and Douglas reached approximately 3,000 residents, largely driven by employment and support demands of several small to mid-size underground gold mines in the region. By 1904, the value of the cumulative gold production of the Alaska Treadwell was five times greater than the purchase price of Alaska in 1867 (Kelly, 2010). By the turn of the 20th century, economic growth in the Juneau-Douglas area relied on supplies delivered from the lower 48. Passenger and freight shipping lines required 3 to 4 days to make the one-way trip from Seattle to Juneau. Established shipping routes required experienced crews due to navigation hazards and adverse weather conditions. Even with precautions at the time, steam ships and freighter vessels experienced breakdowns or encounters with natural hazards that resulted in damage or in some cases, sinking. Interestingly, with no roads or railroads connecting Juneau to other communities in southeast Alaska, Juneau still relies on seaborn shipping in the 21st century.

Jan 1, 2019

By P. R. Bradley

NO thought had been given to deep level mining at the Alaska Juneau mine prior to 1930, but in that year a prospect winze was started and continued for 1000 ft. vertically below the main haulage or adit level. The point at which this winze was started was selected entirely by the prevailing physical conditions, such as proximity to established workings, convenience, and the presence overhead of a substantial pillar of dimensions sufficient to lo¬cate the sheave wheel and loading pocket. It was, therefore, with some surprise that the unusually high-grade ore found just below the collar of the winze persisted, with certain vari¬ations, to a full depth of 1000 ft. vertically. Likewise this unusually high-grade ore was found to persist on the various crosscuts driven on levels at 200-ft. vertical intervals. To be brief, this deep level work found richer ore than any yet found in the mine over like areas, and inasmuch as the area was sufficient to plan for extensive deep level mining, plans for such work were given extended consideration.

Jan 1, 1936

By Russell A. Carter

Alaska is a land of immense proportions and resources. Its very name, derived from an Aleut term, means "The Great Land." Yet, in a state slightly larger than Texas, California, and Montana combined, there are presently only two-large scale mines in production, excluding dredge operations. Once referred to by its territorial governor as "a storehouse of minerals," Alaska is, in the opinion of many industry observers, at least 20 years away from a healthy, productive mining industry. The mineral potential of the state is tremendous: coal deposits on the North Slope alone have been hypothetically pegged at 1.5 trillion tons. Copper-zinc deposits on the south flank of the Brooks Range are conservatively estimated to be worth $4 billion to $6 billion. However, the problems facing mineral development are of equal magnitude, and include:

Jan 11, 1976

By D. S. Case

"Following a brief explanation of the land arrangements under the Alaska Native Claims Settlement Act, this paper will examine both a mineral exploration agreement and a mining development agreement negotiated between two large mining companies and two different Alaska Native institutions. One of the institutions is a village corporation involved with an exploration agreement and the other is one of the Alaska Native regional corporations, which is party to a mining and development agreement with Cominco Alaska for the development of the Red Dog lead and zinc mine.Special attention will be given to the factors to be considered when dealing with small aboriginal owners with few resources in the context of an exploration agreement, including development issues which must be considered early in the process. The paper will also discuss the unique royalty and taxation structures developed for the Red Dog Mine Agreement as well as environmental issues. The paper will also consider the ways in which the cultural and differing economic interests of an aboriginal owner and a large mining company have been accommodated in the both the exploration and development agreements"

Jan 1, 1998

When defining a ?megaproject,? one need only to look at Seattle, WA?s State Route 99 Alaskan Way Viaduct replacement project. This $3.1-billion project is one of the largest of its kind in the world, and includes the use of the world?s largest tunnel boring machine (TBM). However, for as large as the Alaskan Way project is ? especially given the size of the TBM being used ? there are several other megaprojects underway around the world. Each has its own challenges that require innovative design techniques and financing arrangements, as well as variations on established tunneling technologies. So it was that 266 tunneling and underground construction professionals ? owners, contractors and engineers ? convened in Seattle in November for the Cutting Edge Conference on Megaprojects. This was the second joint meeting between the Underground Construction Association of SME and the North American Tunneling Journal. The first joint conference took place in April 2012 in Miami, FL and attracted 238 attendees. A third joint conference, to be held in 2014, is in the planning stage. The key reason Seattle was chosen as the site of the megaprojects conference is the Alaskan Way Viaduct project. Before the conference began, many of the attendees were able to visit the project and get a close look at Bertha, the Hitachi Zosen earth pressure balance TBM that is boring the tunnel. In addition, the conference included an exhibit that attracted 20 industry suppliers, up from 10 the previous year in Miami. The 25 presentations during the two-day conference covered all aspects of the tunneling and underground construction of megaprojects. Topics included the Alaskan Way Viaduct project; considerations for procurement and contracting; political risk, financing and insurance; international megaprojects; risk and risk sharing and project delivery. Each session concluded with panel discussions.

Dec 1, 2013