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By Magnus Troilius

SINCE the discussion on steel rails in America has forcibly drawn attention to the value of chemical analysis, if not as a necessary stipulation, at least as a guide to control the usual mechanical tests, some doubt has been thrown upon the accuracy of the analytical results obtained by different chemists. To any one having the least acquaintance with chemistry, it is quite clear that if exactly similar results are to be obtained from the same borings of steel, exactly the same methods must be used by the different analysts. Hence the necessity (if complications are to be avoided) of establishing what I may call standard or normal methods, to be used both by the inspectors and by the chemists at the works. Remembering that the application of chemistry to steelrail inspection is yet in its infancy, it is of great importance to possess a perfect acquaintance with the best methods in use. Being myself a grateful pupil of Professor Eggertz, of the School of Mines in Sweden, it occurred to me, two years ago, that I could not do better than start a laboratory of my own, and engage one of his pupils, Mr. Troilius, for the purpose of analyzing the steel borings from mechanically-tested rails, so that I might thus obtain without delay thoroughly accurate determinations. Moreover, in order to carry on the operations in perfect accordance with the methods used at the steel works in England and Germany, where I had to control the manufacture, I deemed it desirable to allow Mr. Troilius to go through a course of training at these works; and I gladly seize this opportunity of expressing my grateful acknowledgments to several works in England and in Germany for affording every facility for such an exchange of information as mas found necessary in arriving at the best analytical methods to be used.

Jan 1, 1882

By Charles A. Ashburner

THE appliances which have been proposed, and the modifications in the construction of boiler-furnaces which have been made for the prevention of smoke, and the utilization of what are ordinarily called the waste products of combustion, have been innumerable.

Jan 1, 1882

By Jeffrey Goodwin P. E., Melih Demirkan Ph. D. P. E., Kevin Tehansky P. E.

Just an hour drive down MD 301 from National Harbor, construction to replace the Governor Harry W. Nice Memorial/Senator Thomas ‘Mac’ Middleton Bridge (HNB) began in spring of 2020. The Maryland Transportation Authority (MDTA) contracted with Skanska-Corman-McLean (SCM) to deliver a new US 301 bridge spanning 1.9 miles from Maryland to Virginia over the Potomac River aiming to improve capacity, safety, and access of the roadway. The project area presented a geotechnical design challenge due to the installation of new bridge foundations in the problematic soils of the Atlantic Coastal Plain alluvial deposits. With the existing bridge remaining in service during construction, and the site’s logistical constraints placing new pile driving operations near existing abutments and piers, a complex instrumentation and monitoring plan was developed to ensure public safety throughout the project. This paper discusses the geological conditions of the project area, the collaborative approach of various design team members to develop an appropriate monitoring plan utilizing various instrumentation, an understanding of baseline conditional movements of the existing bridge, and impact response of adjacent construction activity to help deliver effective new bridge foundations while protecting the old ones.

Oct 1, 2022

By C. M. Brinckerhoff

Much has been written in the mining technical magazines about the caving system. Many of these articles were published in the Transactions of the American Institute of Mining Engineers prior to World War II. In recent years little has been written on mining methods or on the detailed planning always required. Block caving had primarily been used to mine deep copper ores in Africa, the United States and in Chile, although other ores had been mined by this same system. Asbestos ore had been caved in Canada, tin ore in Bolivia, molybdenum ore in Colorado, iron ore in Wyoming and Sweden, and limestone in California.

Jan 1, 1984

By Eugene McAuliffe

THE last obtainable figures of the value of the coal mining investment are those contained in the U. S. Census Reports, from data gathered in 1919. The values shown therein and set forth below cover lands and equipment and do not include distribution and marketing facilities. The working capital necessary to meet pay rolls to purchase material and supplies and workmen's compensation insurance are likewise excluded.

Jan 1, 1926

By Frederick Laist

I AM APPRECIATIVE of the honor you have done me in electing me to membership in your Society. I value the contacts with men of imagination and ideals which this implies. I am grateful for the recognition of such small contributions as I may have made, or helped to make, to the vast fund of scientific and engineering knowledge. We like to think, as we grow older, that our lives have not been purely parasitical, and that through our efforts some forward step, however small, has been taken toward improving conditions under which we live and do our work. In these days of industrial depression, we hear much criticism of our "machine age." Modern engineering, mass production, the complexity of our lives, all come in for some share of blame. The farmer is said to have been spoiled by the tractor and the gang plow, the factory worker has become a slave of the assembly conveyor, the scientific worker is no longer free but has sacrificed much of his individuality to the research organization of which he is a part. We wonder whether our work as engineers has been worth while and whether our striving after more efficient ways of doing things has been a curse to mankind rather than the boon we thought we were conferring.

Jan 1, 1932

By C W. Davis

Every diesel engine emits approximately 100 million nano diesel particles (nDP) per cubic centimetre of raw exhaust. Each nDP has a diameter of between 50 and 70 nano metres or 1/100th the size of red blood cells (diameter of between 6 and 8 microns). When inhaled, some nDP pass through the lungs and penetrate all body tissue [1]. Europe and North America have recognised and are addressing the long term health problems posed by nano diesel particulate matter (nDPM) across their societies [2.3]. Australia has been slow to recognise the issue, at both a societal and mining industry level. There are chronic health effects for every underground miner and serious legal issues for mining companies with increasingly stringent Occupational Health and Safety legislation being implemented at a state level across Australia. This paper will review progress within Australian society and more particularly the underground hard rock mining industry, particularly in Western Australia (WA).

Mar 15, 2021

For handling rough rock, the shovel-train system is unexcelled. The ideal application is a physically large, but not excessively deep, open-pit mine from which the coarsely blasted ore and waste must be transported distances in excess of three miles. If, in addition, a high production rate is to be maintained, railroad haulage will probably afford a lower cost per ton transportation than will any other haulage method. Relatively gentle grades must be employed- usually 3% for uphill hauls and 4% for downhill hauls. The greater the differences in elevation the greater are the railroad track grade space requirements. By way of illustration, a 3% ramp out of a pit only 300 ft deep must be almost two miles long. Mainline track locations should be selected carefully so that the frequency of movements during the life of the mining operation is minimized. This applies both to ore and to waste haulageways. Such moves are not only expensive but difficult to execute without adversely affecting production rates. The large mine affords greater opportunities for judicious location of semi-permanent trackage.

Jan 10, 1967

By T. G. Joseph, A. Chamanara

ABSTRACT: The chicken and egg scenario — where adverse truck motions cause ground deterioration and poor ground profiles cause adverse truck motions — is a downward deterioration spiral dominating our industry. If we remove one action, the reaction stops. A simple truck to excavator load data analysis and wireless communication system is outlined, which will provide visual assistance to the excavator operator in achieving improved load placement and balance in a truck body. This will reduce subsequent hauler duty cycle adverse motions and g levels that contribute to structural fatigue, higher tkph, reduced tire life, and ongoing maintenance of haul roads.

Jan 1, 2012

When I wrote the Railroad portion of "Mining Engineering" magazines 94 Powder River Basin (PRB) Coal Article I described to you some definite destinations the Railroads had in mind. As with many destinations, the ones I wrote of turned out to be merely stops on the way to places that we have yet to reach. Somewhere along the way we discovered that making it better is a continuous process not just something that you can do in phases I, II, III, & IV. We always knew this I suspect, but perhaps not at the awareness level that exists in RR environments in 1997. The purpose of this article is to update the 94 article, which I could do very quickly. Everything I told you we were going to do in 94 is done, end of story! But in addition to making it a very short article it would not be telling you the things RR has done beyond what we were planning in 94 and for the future.

Jan 1, 1998

By G. S. Anderson

PRIOR to 1912 the only rail outlets for a large part of the coal regions of Carbon and Emery Counties. Utah, were over single-track lines of the Southern Utah R.R. and Castle Valley Ry. Companies, forming a route extending from Mohrland and Hiawatha, Utah, to a point of connection at Price, Utah, with what is now The Denver and Rio Grande Western R.R. Co. These two tap lines were poorly and inadequately constructed, with impracticable grades, lacking in equipment, and incapable of being put into condition to serve this region and handle the output of the mines, to say nothing of making possible increased production and new development. Any plans for the new development and increased output necessarily involved new and adequate railroad service. It was essential, not only that additional facilities be provided but that these facilities be in the form of an efficient and up-to-date railroad providing an independent through operation from the coal mines to a point of direct connection with the lines over which the product would be distributed to consumers. For this purpose, the Utah Railway Co. was incorporated in

Jan 1, 1948

By B. J. Timmons

An initial point that I would like to make very emphatically?and as our title might erroneously suggest for those of you old enough to remember . . . Peter Harben and myself do not intend to shoot ourselves in the foot. We derive our livelihood from a number of aggregate, industrial and other minerals producers, both here in the United States and outside. This paper, therefore, is a fence-straddler or for information purposes (we hope) only, rather than any "fur or agin" stances. In essence, some of you may consider it a U.S.G.S. publication! In fact, we hope that it serves to inspire aggregates producers to do some radical thinking, to promote introspection, and to that end it would benefit both domestic and foreign producers. The title could be shortened into a brief question of "Aggregates Travel?" with an emphatic no for the answer. In the past, the success of a construction materials venture depended upon your ability, through siting, to provide the customer f.o.b. the job site, a product at the lowest possible cost.

Jan 1, 1987

By K. C. Kocsis

"Diesel-powered equipment has allowed the mining industry to raise production rates and significantly improve productivity, as it is rugged, mobile and reliable, but its widespread use in underground mines has generated concerns regarding the exposure of mine workers to harmful diesel engine exhaust gases and particulate components such as diesel particulate matter (DPM), which has recently been classified as a human carcinogen by the International Agency for Research on Cancer. The agency expressed further concerns that workers’ exposure to high DPM concentrations can increase the risk of cardiovascular, cardiopulmonary and respiratory illnesses. Three emerging technologies could have the ability to replace dieselpowered equipment and remove DPM from underground mines: fuel-cell-powered mining equipment, battery-powered mining equipment and advanced material handling systems. This paper reviews them and assesses whether they have reached the point where the pollutants emitted by diesel-powered equipment can be removed from underground mines through the introduction of zero-emission mining equipment and power systems. Information is also provided from the results of a feasibility study, including a detailed cost benefit analysis, carried out at six Canadian and nine U.S. underground mines, which looked at the possibility of replacing diesel-powered production equipment with fuel-cell-powered equipment. The remarkable pace at which battery technology is progressing is also reviewed, and the feasibility of replacing diesel-powered mining equipment with battery-powered equipment is assessed. IntroductionHazardous pollutants in underground mines. Why is it important to remove diesel particulate matter (DPM) from underground mines? Over the past 40 years, diesel-powered equipment has allowed the mining industry to achieve rising production rates and major improvements in productivity, as the diesel engine is an economical source of power and diesel-powered equipment is usually rugged, mobile and reliable. On the negative side, the toxicity of some diesel exhaust gases is well known (Grenier et al., 2001), and the widespread use of diesel-powered equipment in underground mines has generated increasing concerns about the occupational exposure of mine workers to harmful diesel engine exhaust gases and particulate components such as DPM. Diesel equipment also entails other hazards like heat and humidity. Exposure to excessive heat can cause heat illnesses, such as heat rash, heat exhaustion and heat stroke (Donoghue, 2004; Roghanchi et al., 2016), and a hot and humid underground environment negatively affects the efficiency of the workforce, which may result in a decline in production output (Roghanchi et al., 2017)."

Jan 10, 2017

By Frank E. Lathe

During the war the National Research Council at Ottawa sent out questionnaires to the managers of nearly all the industrial plants in Canada. Inquiry was made as to the research equipment possessed, the number of research workers employed and the nature of the research problems which still remained unsolved. Practically all the companies reported that they had no special facilities for research, had no re-search workers and did not require the assistance of the National Research Council-because they had no research problems. Perhaps we have here one of the chief reasons why certain of our manufacturers find themselves unable to meet foreign competition. For hundreds of years the Indian tribes of northern Chile worked, in a small way, the copper deposits at Chuquicamata. They had no research problems and made no striking success of their mining operations. Then came an American company with a research problem, which they proceeded to solve. To-day the stock of that company has a market value of about $140,000,000.

Jan 1, 1926

By John L. Ellenberger

Virtually no two mines operate with the same geographic, geologic, and mining conditions. It follows chat problems vary with the conditions from mine to mine or often from one section to another in the same mine. Actual situations are described, and a technique of "stacking" maps to predict hazards is presented. Two case histories of the use of multiple overlays are de- scribed. The first deals with a property that was examined before the start of mining. The second is a property in which severe ground control problems were encountered and the relationship between the problem areas and known conditions were found to be related.

Jan 1, 1981

By Kirlk Yeager

"Ammonium nitrate (AN) is commonly mixed with a wide variety of additives to produce specialty formulations. Two additives commonly utilized are sodium nitrate (SN) and sodium nitrite (SNi). Application of the nitrite is primarily limited to gassing of emulsions. The nitrate, however, is incorporated in a wide variety of formulations. The effect of both these materials on the thermal stability of AN was examined. Experiments initially utilized lab-scale testing methods (sub-milligram sample size), such as differential scanning calorimetry (DSC), with scale-up to cook-off analyses (16 g) eventually applied. Labscale testing indicated that the presence of SN and SNi (both at 5 wt%) produced no harmful effects on the thermal stability of AN. The cook-off results did not agree with those from the lab-scale analyses, with both SN and SNi creating tremendous thermal destabilization of AN. These effects were seen at additive levels as low as 0.1 wt%. When SNi was employed as the additive, cook-offs became violent enough to create explosions in the testing apparatus. Although SN did not create as spectacular a destabilization, it did lower cook-off temperatures to approximately the same level as SNi. The dangerous situation created by SN andSNi seemed to be limited to cook-offs conducted in sealed vessels. If the SN/AN or SNi/AN formulations were allowed to cook-off in vented vessels, the thermal destabilization of AN did not occur. These results seemed to indicate that even “trace” amounts of what might ordinarily be viewed as benign additives could create significant destabilization of AN-based explosives under proper circumstances. Conditions created by blocked pumps, or deep boreholes could well overlap those produced in sealed cook-off vessels. In addition to showing the hazards potentially created by “benign” additives, the study also stressed that experiments designed to evaluate thermal hazards must include duplication of field variables to the fullest extent possible. "

Jan 1, 1999

By William Firmstone

On the 19th December, 1833, a patent was granted to F. W. Geisenheimer, for smelting iron ore with anthracite. In his claim he says: " Sixthly, though I cannot, and do not, claim an exclusive right of the use of heated air, for any kind of fuel, nevertheless I believe to have a right to claim the use of heated air, applied upon, and in connection with, the said principle and manner discovered by me, to smelt iron ore in blast-furnaces with anthracite coal, by applying a blast of air in such quantity, velocity, and density, or under such pressure, as the compactness, or density, and the continuity of the anthracite requires, as above amply and fully described and illustrated." Dr. Geisenheimer made experiments in smelting iron ore with anthracite at the Valley Furnace, near Pottsville, but he failed to carry out to good practical results the principles enunciated in his patent. In the .Joozcrnal of the Franklin Institute for February, 1838, a communication was published that was made by Mr. George Crane, of the Yniscedwyn Iron Works, South Wales, to the British Association, in September, 1837. On the smelting of iron with anthracite coal, Mr. Crane states therein, that he began the use of anthracite with hot-blast on the 7th February, 1837, in a cupola blastfurnace, 41 feet high, and 10 feet across the boshes ; product, 34 to 36 tons a week. Mr. Crane goes on to say, "It may not be uninteresting to be informed in what matter the idea first occurred to me of applying a heated blast to anthracite coal. One evening, after I had placed a piece of it upon my parlor fire (which had before been made up with bituminous coal), arid had allowed it to arrive at a red heat, upon applying as fierce a blast to this piece of coal as I could raise from a pair of bellows, I noticed a black spot or mark

By Rossiter W. Raymond

The most important event in the history of mining in the United States was the discovery of gold in California, which led to the rapid development, not only of a new industry, but of a new empire. The settlement of the Pacific slope was making but slow progress under the inducements of a scanty commerce in furs and hides. The liberal grants offered by the government to agricultural pioneers in Oregon had attracted to the Willamette valley and other favored points in that territory a limited population; hot the government of the Mexicans in California was positively unfavorable to enterprise. It is true that gold was known to exist in the country. Rumors of it were current among the trappers, and placers had actually been worked in what is now Los Angeles County; but the padres of the neighboring mission of San Fernando had discouraged the business as demoralizing to their flocks; and the existence of the precious metal was not widely known; still less was its distribution northward suspected. The discovery of gold, January 19th) 1848, at Sutter's saw-mill, on the south fork of the American River, afterward famous as Coloma, in Eldorado County, was the beginning of the new epoch. This discovery was made by James Wilson Marshall, a partner in the mill, who observed in the debris washed down by the tail-race a glittering fragment of a mineral unknown to him. Suspecting it to be gold, he sought for further specimens, and obtained, in the course of a few days, several ounces of it. Tests subsequently

By E. J. Kenaedy, E. H. Robie

THOUGH the fall meeting of the Coal Division was held in the heart of the anthracite section, at Hazleton, Pa., the bituminous industry was well represented also, and the two groups found much common ground for discussion. The' technical part of the program was confined to two sessions in the morning and afternoon of the first day, Friday, Oct. 14, the evening and the following day being reserved for field trips and social functions. The attendance more than met the expectations of those in charge of the arrangements; there seemed no hint of depression here.

Jan 1, 1932

By Boyd Davis, Vladimiros Papangelakis, Joshua LaMarre, Jan de Bakker

"HCl leaching using molten salt hydrates has the potential to improve the extraction of nickel from laterite ores. However, as in other HCl leaching applications, recovery of HCl is key to process economics. Spray pyrohydrolysis, which is used in current chloride-based flowsheets, is associated with a high energy cost. The authors have developed a proposed laterite leach circuit using an alternative HCl recovery route. The leach circuit envisions a leach by concentrated (33%) HCl in an MgCl2 molten salt hydrate (MSH) or brine medium, followed by Ni/Co recovery and iron precipitation. Magnesium and chloride are precipitated from solution as magnesium hydroxychloride; this hydroxychloride is thermally decomposed to produce HCl gas. The proposed flowsheet employs a chloride leach circuit with simpler equipment and lower energy cost than in the conventional practice of pyrohydrolysis. Laboratory work investigated key aspects of the flowsheet, including precipitation of magnesium hydroxychlorides and their composition; magnesium hydroxychloride thermal decomposition; and iron control.Introduction As sulphide nickel ores become harder to mine and more complex to process, laterite ores will increase in importance. Laterite ore deposits can be divided into two main mineralogies. Limonite ores consist mostly of hydrated iron oxide, FeOOH, with 1-3% nickel substituting for the iron. Saprolite ores consist of iron-magnesium silicates, (Fe, Mg)2Si04, again with some nickel substituting for the metal ions. Limonite ores can be treated using the HP AL (High Pressure Acid Leach) process, in which the ore is reacted with sulphuric acid at high temperature in an autoclave. HP AL, however, cannot in general be used to treat saprolite ores because the magnesium enters solution and consumes sulphuric acid, which results in excessive spending on lixiviant. It is therefore desirable to find a hydrometallurgical process specifically for saprolite ores that can provide better results than the treatment options currently available."

Jan 1, 2011