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By D. O. LIVINGTON

(Presented by invitation at a meeting of the Spokane Local Section of the institute, Feb. 17, 1912.) THE Pilares de Nacozari mine is located in Sonora, 75 miles south of Douglas, Ariz. The town of Douglas is on the International Boundary and is the place at which the ores from the Bisbee mines are smelted. The Moctezuma Copper Co. owns the mines at Nacozari, and the copper-concentrates shipped to the Copper Queen smelter, at Douglas, make a good smelting-mixture with the Bisbee ores. The Moctezuma Copper Co. and the Copper Queen smelter at Douglas, as well as the railroad from Douglas to Nacozari, are owned by the Phelps Dodge Co. The ore-deposit occurs in the form of a large ellipse with a major axis of approximately 2,000 ft. and a minor axis of about 600 ft., the major axis bearing about 90 W. of N. The whole of this ellipse is more or less mineralized; the surface being principally an iron gossan with some occasional copper-stains. Below the oxidized zone, which is not more than 50 ft. deep, the minerals are pyrite and chalcopyrite, with occasional seams of chalcocite, the latter being rare. There appears to be no well-marked zone of secondary enrichment, the oxidized gossan over the greater part of the deposit changing suddenly to what is apparently the original unaltered ore. The copper-values are concentrated around the perimeter of the ellipse, and it is principally around this perimeter that the mining is done. The ore mined averages a little more than 3 per cent. of copper, with a small amount of silver, less than an ounce per ton. Some ore of considerably higher grade than this has been shipped, however, but the above average is of the mill-run. The ore is wider near the two ends of the ellipse than along the sides, and is mined in some cases to a width exceeding 200 ft. The country-rock for the first vertical 500 ft is a volcanic acid breccia, probably rhyolitic; below

Sep 1, 1912

By Lei Wang, Qi Zheng, Xiao-kui Che

"The wastewater emitted by gold chemical industry contained vast of different heavy metal ion, such as Zn, Cu and Ni etc. Among them Zn is the main ion in the waste water which causes the serious environment pollution. A method of preparing a kind of resin which is used for the removal of Zn by magnetic adsorbent was developed and was applied in practice. This adsorbent is a chitosan made of a kind of Fe3O4-chitosan modified by epichlorohydrin. The adsorption capacity of the absorbent and it was concluded that under the laboratory conditions, the maximum adsorbing capacity of this adsorbent could be 287.58 mg/g. The absorbent was also applied in the wastewater emitted by a gold industry in Shandong province. Its performance was tested and the result showed that the concentration of Zn ion in the wastewater was reduced from 0.58 mg/L to 0.0174 mg/L. What is more, the adsorption rate could be more than 97% when the dosage was 100L/m3 after adsorbing for 1h. KEYWORDS Selective, preparation, laboratory experiments, industry experiment, comparation INTRODUCTION Currently, most gold chemistry use cyanide to leach gold ore. Many different metals participate to this reaction besides the gold ion in this processing, so that the composition of the water is very complex. The waste water emitted by gold chemistry industry contains large amount of heavy metals. Definitely, if it was discharged without any treatment, the water would threaten the environment. The recuperation of any ion in the water would mitigate the pollution. Ion exchange resin, which is an effective material to do the water treatment with low cost, became widely applicated in this field [Yu-jiao Wang,2013]. Different kinds of resin were developed and the influence factors such as pH, adsorption properties and selectivity for different ions were investigated [CA Cruz et al,2018; PawanKumar et al.2016; Y Zhang, et al,2010; and ShengingSun, Aiqin Wang, 2006;]. The waste water mentioned in this article has a high Zn concentration, so a magic resin for Zn adsorption selectively we designed was used to manage this water. And the recovery of Zn could not only contribute to pollution abatement but also a best way to settle a dispute to the short of Zn resource. So the article mainly describes the preparation and the application of a kind of magnetic adsorbent used for the removal of Zn both in laboratory and industry. The aim of this article is to compare the effect of this resin in industry and laboratory?"

Jan 1, 2018

By J. Sidhom, W. Fourie

"As the mining industry continues to face difficult challenges the need to persistently focus on productivity and utilization of labor and equipment costs will intensify. With these challenges in mind, Joy Global is helping to bring mining performance and analytics to the next level. By evaluating underground haulage, a significant component of the Room and Pillar mining value stream, variables have been identified and sensitivities have been performed to show opportunities to balance and streamline throughput. As a result of applying operational excellence tools to the mining environment, Joy Global is seeking to optimize mining performances by limiting waste, simplifying the process, increasing productivity and machine utilization, as well as removing workers from harm’s way. These days it’s not enough to work harder; mines have to work smarter. Improving efficiency, reducing costs, increasing safety: these are no longer ‘nice to haves’, they are ‘must haves’. Starting with the best products and the right people is a first step, but then what? How do mines take their operations from just OK to being a top performer? By using operational excellence principles aimed at eliminating waste, simplifying processes, automating where possible and removing people from harm’s way. The fundamentals of operational excellence (OpEx) are based upon the DMAIC process, which stands for define, measure, analyze, improve and control. DMAIC is an improvement cycle that helps with, for example, haulage optimization by: defining the issues and problems in the process as well as the areas of improvement; measuring and collecting mining operational data by time study and equipment monitoring system; analyzing through sensitivities and production modelling to determine root causes; then improving the performance and controlling the operation. Joy Global uses Joy OpEx or ‘lean’ principles inside its organization to drive efficiency, but it also helps its customers employ them to achieve new levels of productivity and safety. These same principles can be applied in most situations to streamline processes, improve operations and deliver value. As applied to mining, OpEx is seen as moving the needle on value creation by first identifying the value stream, then analyzing the areas that are not optimized. Once defined, these areas are ‘designed out’ of operational processes to create an automated operational flow. At a US coal mine, Joy Global was brought in to apply Joy OpEx principles to optimize mining and haulage to improve productivity and reduce costs. This multi-phase process started by defining the existing systems challenges to start finding areas for improvement."

Jan 1, 2017

By Henry Kreisinger, WALTER T. RAY

This bulletin contains a statement of certain results that will be embodied in a report describing investigations of the combustion of fuel made by the United States Geological Survey and the Bureau of Mines in a specially constructed long furnace. The furnace forms part of the fuel-testing plant at Pittsburg, Pa., which was established and equipped by t.he Geological Survey, but passed under the control of the Bureau of Mines on July 1, 1910, when a t.ransfer of fuel-test.ing investjgations, authorized by act of Congress, became effective. The work discussed in this bulletin was done under the direction of the Geological Survey. The furnace was designed and built for an experimental study of the processes of combustiop, this study being part of a comprehensive plan for testing fuels to determine their heat value and the manner in which they can be used to best advantage. Although the main object of the researches made with the furnace by the Geological Survey was to examine critically the production of sensible heat by combustion along the path of the gases rising from the fuel, an interesting as well as important side problem developed in the study of the simultaneous dissipation of the heat through the walls and roof . of the furnace. Thus incidental data were collected on the temperature gradient through the walls at several places. These temperature data. (together with the heat conductivity of the material of the walls) formed the basis for calculating the heat dissipated through the walls. The object of this report is to present and discuss these temperature data. The discussion particularly concerns the air-space type of wall construction as compared with the solid brick wall or walls type, in which the air space is filled with some solid material of low heat conductivity. The conclusion of the authors, which perhaps will surprise some readers, is that, so far as loss of heat is concerned, a solid wall of brick or any ordinary material is preferable to a hollow wall of the same total thickness, especially if the air space in the hollow wall is near the furnace side. There is a general belief that l?ince air is a poor conductor of heat, air spaces built into the walls of a furnace will prevent or reduce heat dissipation through the wa.lls. Although there may be instances of furnace walls in which such construction reduces the rate of heat flow through them, yet as a rule the effect of the air space is just the opposite. While the heat does travel very slowly through the air by conduction, it leaps over the air space readily by radiation. Although this latter mode of heat propagation is common in nature, the laws governing it are not generall;y known and are seldom taken into consideration when furnace walls are being designed. It may be stated here that the quantity of heat passing through a. portion of a solid wall by conduction depends on the difference between the temperatures of the two planes limiting the portion of the wall. The quantity of heat that passes across the air space in the waH depends on the difference of the fourth powers of the absolute temperatUI: es of the surfaces inclosing Hie air space. It follows that, in case the heat. passes by conduction through the solid'portion of the wall, the loss remains approximately the same so long as the temperature of the two limiting planes remains constant, no matter what may be the temperature of the two planes. On the other hand, the heat passing across the air space by radiation increases rapidly with the temperatures of the inclosing surfaces, although the difference between these temperatures may remain constant. This feature will be shown by curves in the latter part of this paper and thoroughly discussed. The important point is that the air space, which is advantageous in the walls of a refrigerator because the temperatures are low, is objectionable in a furnace wall because the temperatures are high. It is customary to put air spaces in furnace walls between the firebrick linings and the common brick. Usually the fire-brick lining is only half a brick thick, which construction brings the air space too close to the furnace. The result is that the temperatures of the surfaces inclosing the air spaces are too high, and in consequence too much heat is radiated across the spaces. The heat passing through such walls would be much reduced if the air spaces were filled with brick, or, better, with some cheap nonconducting materials, such as ash, sand, mineral wool, etc. Even where the fire-brick lining is one brick thick (9 inches), the temperature in the furnace may be high enough to raise the temperatures of the air-space surfaces so much that the heat radiated across the space will amount to more than would the heat conducted through a filling, were the filling only common brick. This last statement is amply justified by the data here presented.

Jan 1, 1911

By Roderick Guthrie

Gas injection into liquid steel baths is widely practiced, ever since the early days of Bessemer’s pneumatic steelmaking process. What has not been fully appreciated is the critical role of bubble sizes for delivering higher quality commercial steels than is presently possible. This was first proposed by Prof P. Hayes and his research group. Using a full-scale water model of a typical 4-strand Ladle-Tundish-Mold system, we demonstrate the potential advantages of modifying a typical ladle shroud, to generate microbubbles within the water flowing into the tundish. This is possible by taking advantage of high shear rates and turbulence kinetic energy available in that region. These microbubbles enhanced the removal of “micro-inclusions” (hollow glass microspheres) in the 5–50 micron size range, to the upper surface of the tundish. There, they were absorbed into an overlaying “slag” phase. Accompanying CFD studies confirmed that no microbubbles in the size range generated (500–900 μm), pass through the submerged entry nozzles into the moulds.

By David R. Gossett

For the 22nd year, the chance to exchange knowledge, experience and business cards drew hundreds of mining and phosphate professionals for a two-day regional Phosphate Conference in Lakeland, Florida Nearly 400 people participated in the October conference, which focused on the phosphate industry?s future success. There were 41 exhibitors, 13 program advertisers and 23 sponsors among those supporting the conference. It was chaired by David Gossett, 2006-2007 SME Florida Section Chairman. In the opening panel session that he chaired, John Garlanger (SME) of Ardaman and Associates posed the questions; ?How successful has the industry been? How do we measure it and what factors contributed to the industry?s success? How long will the ethanol boom last? Can the industry obtain the permits it needs to mine for the next 30 years? Can the industry attract and retain the quality of workers it needs??

Jan 1, 2008

By Shigehisa Endoh, Hitoshi Ohya, Atsushi Inaba, Shigeki Koyanaka

"Recycling should be promoted to keep the global environment. However, it is difficult to detennine the quantitative impact. A life cycle assessment is one of the most reliable methods to estimate the global environment impact.Exergy is useful like entropy when considering the sustainable development. All of our activities have been obtained exergy resources and/or energy itself and throw away waste and/or waste heat. We are trying to use exergy to estimate the quantity of energy and matter for resource accounting. For recycling plastic, plastic has two aspects; material and energy source.The environmental assessment of plastic recycling suggests that the exergy reduction of the entire system is estimated by the yield of matter and the process efficiency. The material recycling is better than the thennal recycling when the process efficiency is high. However, the thennal recycling is much better for the low efficiency. The transition point is able to be decided by the efficiency of the manufacturing and the electric power generation.IntroductionRecently, many of the global environmental problems have become conspicuous like global wanning, ozone layer depletion and acid rain. Some of the methods like life cycle assessment for solving these problems have been presented. Anxiety concerning the proble1ns of energy and resources has led to a rapid increase in the interest in describing and understanding the conversion processes of energy and other resources in today's society. All human activity is supported by obtaining power and products of high exergy from the environment and throwing away the waste material and the waste heat of low exergy back the environment. However, the total exergy in the whole system becomes absolutely smaller than before.The rate of obtaining high exergy products and energy itself by human activity and the speed, by which waste and waste heat having low exergy are thrown away are too fast to attribute to environmental problems [1-3].A material's use by recycling was often common in a circulating society mainly. A significant amount of energy is consumed during circulation. An environmental impact assessment method for the process or the system has not been devised when both of them are taken into consideration. Even if the life cycle assessment evaluation, which has been correctly used up to now, is applied, it is not sufficient for an overall evaluation concerning matter and energy.The real sustainable development is that the exergy reduction value by all human activities on the earth is kept within the range of the exergy reduction in order to consider the earth as closed stationary system. It is important to evaluate the process or the system by using the exergy, and design them so that the exergy loss may decrease as much as possible. We have to consider what process improvement is the most effective."

Jan 1, 2000

By R. C. Emmett

Waste treatment in the mining industry is by no means a new problem to this field. In a sense, the entire process from ore to finished product is one of waste treatment - the separation of a relatively minor quantity of desired component from valueless material. Where it has been necess-ary or economical to practice conventional waste treatment or pollution control methods, such as dust collection, water recovery from tailings, or impounding of residues for future treatment, this has been done. Generally the containment of hazardous pollutants such as arsenic and cyanide also has been followed in modern times. But it is only recently, with the public outcry for the elimination of all forms of pollution, "that the industry has been forced to solve what often appears to be a myriad of difficult and costly waste treatment problems, or be faced with the alternative of closing down the operation. It is the objective of this paper to describe new as well as conventional approaches to these problems, specifically as might be applicable to liquid-solids separation methods. Host wastes in the industry are present either as solutions or slurries, or can be most advantageously handled by conversion to this form, such as in scrubbing noxious gases and dusts with water. Separation of the solids and purification of the aqueous effluents are, therefore, often the principle problems.

Jan 1, 1971

Research, whether applied or fundamental, is a human endeavour which increases our understanding of nature. It is insufficient to simply observe, explore, record and classify. It i necessary, as well, to fit the observations into a satisfying theoretical scheme; that is, to synthesize. Two examples of successful research programs in physical metallurgy are di cussed from this point of view. A pessimistic view is taken of the prospects for rapid growth of research activities in the Canadian metallurgical industry. THE term "research" is used indiscriminately to describe any intellectual or experimental activity which leads to a change in society. Proponents of various activities, ex-tending all the way from alloy development to subliminal advertising, use the status of the term for special advantage. With the Canadian Government entering upon a project of support to industrial research, it might be well to determine what definition is most in the public interest. As an academic, I have a rather jealous attachment to the definition that research, whether applied or fundamental, is a human endeavour which increases our understanding of nature.

Jan 1, 1963

By Alaina Mallard, Jannette Chorney, David Hutchins, Grant C. Wallace, Jerome P. Downey

Current commercial processes for producing ceramic carbides require temperatures of 1400–2000 °C and often use extensive milling operations to produce a powder product. A process that could reduce the energy requirements of commercial carbide production could allow for these materials to be implemented in a greater number of applications. In this study, tungstate (WO4 2−) and silicate (SiO3 2−) anions were adsorbed onto activated carbon and converted into silicon carbide (SiC) whiskers and a mixture of tungsten and tungsten carbide (W/WC) crystals via carbothermal reduction using inert and reducing gas atmospheres at temperatures much lower than what is required by current commercial processes (950 °C for W/WC/W2C and 1200 °C for SiC). The adsorption process was statistically-optimized via a central composite response surface analysis using DesignExpert 9. Inductive coupled plasma optical emission spectroscopy (ICP-OES) was used to measure, and optimize, adsorption efficiency while the carburization products were characterized using X-ray diffraction and scanning electron microscopy.

Mar 1, 2017

By M. Evertsson, E. Hulthén

"In aggregate production and mining the operators are responsible for controlling and monitoring the process to maintain high plant throughput and safe operation. Operators have to make different decisions to control the process due to changed demand on the operation from both management and conditions of the process. The quality of the response and the time it takes for an operator to respond to altered demand relies on what information is available and the experience of the operator. In this work a dynamic simulation platform has been developed to be used for operator training. Models for representing production units and process control for plant simulations have been developed and implemented in MATLAB/SIMULINK to simulate time-dependent plant behavior. Stochastic and scheduled events are included using the discrete events simulation toolbox SimEvents. The human-machine interface was developed using the human-machine interface software ICONICS. The operators’ cognitive process, in interpreting the plants semantic, has been studied by observations and with informal interviews with operators. This was done to get information about the daily operation and the problems that occur in the process. By interacting with operators that experience different physical interactions with the process; more qualitative e-learning software for supporting operator training in a dynamic operator environment could be developed. The quality of the operator training environment was evaluated with a usability study that was performed with operators and others within the production."

Jan 1, 2014

By Richard W. Amerman

The final cost and quality of a project employing equipment, labor, and materials is dependent upon the expediency and extent to which each of these parameters are used. An ideal solution then, would be one in which three solvable equations were given for each particular situation. The equipment, labor, and materials could then be solved for, and the perfect job would result. In reality, however, the ideal and most economical solution is seldom attainable by solving three given equations. Therefore, knowledge, experience, and sometimes guesswork must be relied upon when correlating equipment, labor, and materials. Drilling and blasting, in particular, is one operation which normally involves more uncertainty than other operations. It is also an operation in which the outcome is extremely critical for two reasons. First, the cost of the operation that follows drilling and blasting is dependent upon how well the material is fragmented. Second, once the drilling and blasting has taken place, it is impossible to return to the area, without considerable expense, and correct any mistakes that might have been made. Therefore, what is desired is a method by which drilling and blasting operations can be performed yielding optimum results at the lowest cost; this can best be accomplished by having the relationships between equipment, labor, and materials prior to their use. For obtaining best results, the selection of these three relationships must be based on knowledge, experience, and as little guesswork and uncertainty as possible.

Jan 1, 1969

By Samuel B. Christy

At the last meeting of the Institute, several contributions were made to the subject of miners' aid funds. Such matters will always form important factors in the administration of large industrial enterprises. From the frequently remote and isolated position of mining properties, it is a subject that often forces itself upon the attention of the mining engineer. Local conditions are usually so variable that no single method can be found equally well adapted to all localities. At the same time, a study of different types is often suggestive and valuable, and it is with this in view that these notes are presented. The Miners' Fund of New Almaden is a remarkably successful example of what may be done for miners by a wise and at the same time firm management, by simply directing their own efforts and without incurring any great expense to the stockholders,—a practical consideration not without importance in most cases. The quicksilver mines of New Almaden are situated at a distance

Jan 1, 1885

By David R. Wilburn

The U.S. Bureau of Mines investigated the resources, costs, capacities, market relationships, and short-and long-term supply of bauxite, alumina, and aluminum. The 45 evaluated mines and deposits in 14 market economy countries (MEC's) have a demonstrated resource of 8.4 billion mt of bauxite and an aluminum content of approximately 2.1 billion mt. Developed world bauxite resources and existing primary aluminum smelting and refining capacity are sufficient to satisfy demand through at least 1995, when additional properties (with higher cost levels) would need to be developed to satisfy future demand levels. It is anticipated that new alumina or aluminum production most likely would occur in developing regions with large bauxite potential, low-cost energy sources, and a close proximity to refining and/or smelting capacity. An increase in aluminum recycling capacity would help meet future demand increases. A series of network model supply analyses was performed for the period 1988 through 2000. Based on announced future production levels and assuming demand grows at the level outlined in the analyses, model results indicate there is sufficient material available to meet demand until 1998, where-upon an aluminum shortfall is projected. Additional analyses investigated the effect of a reduced growth rate of demand and regional production variations in Venezuela on the international aluminum industry.

Jan 1, 1993

By R. B. Crookston

Oil shales differ from coals in that they contain less carbonaceous material, convertible to volatile hydrocarbons, and more inorganic rock. In all pre-commercial oil shale development, involving extensive full scale mining operations, there have been no explosions. However, large scale mine tests with oil shale dusts by the Bureau of fines showed that propagating explosions could be induced under certain circumstances. Laboratory tests were conducted on a broad spectrum of oil shale dusts to define chemical properties and to seek correlations with subsequently determined fire and explosivity properties. These latter properties, indicative of safety hazards, increased as the Fischer assay oil yield of the dusts increased and as particle size decreased. Laboratory data were used to relate fire and explosivity properties of oil shales to those of coals and other carbonaceous materials and to assist in the identification and evaluation of potential hazardous situations which may be encountered in oil shale mining and processing.

Jan 1, 1978

By John Gross

From the time when man first pounded one rock upon another or used heat and sudden chilling with water to disintegrate rock, the art of crushing advanced but slowly to the mule-driven arrastre and the Chilean mill stage until the advent of power-driven appliances made material progress possible. The combined efforts of manufacturers and operators have made modern machines highly efficient mechanically. Although marked progress has been made along mechanical lines, the theory and conception of underlying principles have not advanced so rapidly. This lack of advance in theory may be attributed to the unfortunate situation resulting from the controversy as to whether the Rittinger or the Kick law is applicable to crushing. Many pages of the technical literature are burdened with theoretical discussions in favor of one or the other of these laws, which have tended to cloud rather than to clear the atmosphere.

Jan 1, 1938

By E. H. BURROUCHS

This bulletin is the third of the series of yearly petroleum bibliographies being published by the Bureau of Mines. The two preceding, Bulletin 149 and Bulletin 165, were for the years 1915 and 1916, respectively. In arranging the references the same general scheme has been followed, but as in those bulletins, several changes and additions have been made in the classifica.tion, the more important being in the classes " Development and production " and "Refining and refineries." German periodicals for 1917 were not procurable and references to articles in those and in other foreign journals that were not available have been credited to the sources from which they were procured.

Jan 1, 1920

By AIME

WE got our chance to talk with Arthur J. Blair at the Annual Meeting at the Pennsylvania Hotel. By two o'clock Wednesday afternoon things had quieted down enough so we had our interview in the foyer to the Ball Room. There were the usual questions. Where were you born? In La Salle County, Ill., on March 26, 1885. Where did you go to school? Northwestern University, B.S. degree in 1906. Where did you start work? For E. J. Longyear right after leaving school. One's ability as a geologist was measured by one's ability to wield a brush hook and ax. He stayed on the job as geologist for three years and then got to thinking about the advantages of a warmer climate. The advantages stacked up favorably, so off he went to Birmingham, Ala., just about the time U.S. Steel took over the Tennessee Coal, Iron and Railroad Co.

Jan 1, 1948

By Trevor R. Ellis

Minerals appraisers/valuers often find great difficulty in attempting to employ the sales comparison approach to the market value appraisal of development and operating stage mineral properties. An important factor generally overlooked is a comparison of net operating income (NOI) margins on a per-unit-of-production basis between mineral properties, whether these be demonstrated or forecast margins. NOI margins can vary greatly between mines or quarries that are producing similar products. Ultimately, the expected NOI margin determines what a buyer is willing to pay for an income-producing property. Here, common criticisms of the sales comparison approach by mineral appraisers are introduced. These are counterbalanced by raising some issues in the way the inputs for the income approach are usually derived by minerals appraisers and by review of some conspicuous examples of the much-too-common misuse or abuse of the income approach in market value mineral appraisals. Example transaction analyses and sales comparison analyses are used to demonstrate the author?s methodology for adjusting units of resource in his transaction adjustment tables. The examples are used as the basis for a discussion of ways to employ adjustments for operating economics and many other factors, while warning against the potential for double counting. The conclusions include a recommendation that minerals appraisers attempt to apply at least two of the three valuation approaches when appraising the market or fair value of development and operating stage mineral properties, the two being the sales comparison and income approaches.

Jan 1, 2011

Jan 1, 1947