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By Daryl R. Tweeton

Bureau of Mines research in in situ uranium leaching includes injection well construction and environmental aspects. Clogging of injection wells is a common problem, and is affected by construction techniques. Part of the clogging can be caused by a low-permeability skin left on the borehole wall if the drilling fluids are not thoroughly flushed out. Certain polymer drilling fluids are less prone to cause clogging than bentonite muds, since a lower solids content can be used. The environmental research primarily involves two contracts. The first describes the environmental impact of in situ leaching and the effect of environmental legislation on leaching; the second describes the cost effectiveness of various methods of restoring ground water quality.

Jan 1, 1978

By K. C. Dean

Discarded automobiles represent the greatest single resource of reusable metals, plastics, and rubber in the United States. This report presents results of Bureau of Mines research, conducted from 1965 to 1983, on separating and recovering useful materials from the scrapped hulks, using old and new metallurgical techniques combined with standard scrapyard methods. The Bureau determined the materials composition of three composite cars designated as circa 1960, mid-1970's, and early 1980's, and used these cars to study smokeless incineration and hand-sorting techniques. In studies on treating rejects from automobile shredders, the Bureau designed a process that included air classification, water elutriation, magnetic separation, handpicking, and heavy-medium separation, and also investigated cryogenics and liquation. Complete recovery of cop-per and other metals was economically made by hand and tool dismantling, leaching, or selective melting of starters and generators. Techniques are also discussed for plastic recovery and waste tire treatment.

Jan 1, 1985

By John Wellington Finch

INVESTIGATIONS by the Bureau of Mines of deposits containing strategic minerals were authorized by what has become known as the Strategic Materials Act (Public No. 117, 76th Congress, Chapter 190. 1st Session). A later act providing an appropriation for the first of four years through which the investigations are to be conducted was signed on Aug. 9, 1939. No time has since been lost as seven field projects already are being vigorously prosecuted, and two others no doubt soon will be in course of execution. Project engineers were at their stations within two days after funds had been made available. Crews have been hired; equipment and supplies have been purchased; 5 bids for diamond drilling have been obtained and the drilling has started base camps have been established: ground has been cleared; and several thousand feet of trenching, test-pitting, and sampling have already been done. At the Reno Experiment Station of the Bureau, a special metallurgical laboratory has been provided to make assays, analyses, and tests upon samples of ores from all projects under investigation.

Jan 1, 1939

By Ballard H. Clemmons

THE future of the steelmaking industry of the Birmingham, Ala., district is closely related to and, in a large measure, dependent on the development of workable, economic processes of ore concentration. Operations thus far in the area have been possible only because of the fortuitous occurrence of iron ore, fluxing stone, and coking coal-all the primary iron-making materials- within a 25-mile radius of the blast furnaces. Commercial ore of the district consists mainly of a 10 to 20-ft hematite-calcite-silica bed locally known as the "Big Seam," a component of the Clinton formation of Silurian Age. At present mining rates, this ore will be available for a number of years. It is largely mined under 1000 to 2000 ft of cover and transported on 15 to 20" slopes that, in some instances, are as much as 10,000 ft long. Under these conditions, particularly with increasing distances from face to portal, mining costs are gradually becoming disproportionately high. Although not a major factor thus far, it should also be noted that the average annual ore output of the district is gradually be- coming more siliceous.

Jan 1, 1950

By Lee W. Saperstein

In surface mining for coal, common practice for the disposal of preparation plant refuse is to bury it. As with surface refuse piles, these buried wastes can ignite and can also lead to ground and surface water pollution. Steps to ameliorate these problems have been devised over the years. C and K Coal Company, of Clarion, Pa., the largest Pennsylvania surface mining company, has incorporated all of these steps and added of few, of their own in their latest disposal practice. In addition to layering and compacting, C and K practices selective placement and dilution to minimize longterm problems.

Jan 1, 1977

By S. H. Ash

A CLAY, sand, and gravel deposit known as the "buried valley" of the Susquehanna River is situated in the Northern field of the anthracite region of Pennsylvania near Wilkes-Barre. The presence of this buried valley and the uncertainty regarding the extent and physical condition of the water-bearing valley-fill deposits have made great care necessary in mining operations to avoid breaking the strata between the mine workings and the valley-fill deposits to the extent that inundation of the mine workings would follow. The principal factor that threatens to cut short the life of the anthracite industry, to curtail production, and to affect the economic structure of the people and business dependent on anthracite for their livelihood is inundation of anthracite mines (6,7).3

Jan 1, 1950

By P. Nicholls

Patent records show that the idea that the burning of fuels can be improved by mixing or pretreating them with chemicals 6 dates back to the early years of the last century. By 1845, English and French patents included the specific beneficiations of elimination or reduction of smoke, soot, and clinker; reduction of the ashes, presumably meaning the total weight of refuse from the ashpit; elimination of sulphur fumes; increase in the rate of burning; increase in the time a given charge of fuel would last; and, in most patents, a saving of fuel. The earlier patents specified additions up to 80 pounds or more per ton of fuel, but after 1860 the quantity was rarely more than 4 pounds. There is no record of the extent to which these patents were commercialized, but after 1884 many American patents were assigned to companies specializing in treatment of coal, so it is probable that the products were marketed on a considerable scale at least as early as that date. From 1900 on, many companies marketed proprietary products that were sold under the general name of "fuel savers." Since its establishment in 1910, the Bureau of Mines has continually received inquiries about these products and, at the request of other govern-mental departments, has tested some used in accordance with the instructions of the purveyors; the results were all negative and, within the accuracy of measurements, the products had no effect on the burning.

Jan 1, 1937

By D. P. Ziegler

Formulas relating economic optimum busbar cross sectional areas to busbar cost, electric price and financial parameters are reviewed and revised. Application of the formulas is illustrated with discussion of the appropriate choice of parameter values and the sensitivity of the optimum to the parameters. The extension of the single busbar concept to optimization of more complicated arrangements of bus for smelting pots is complicated by the constraint of obtaining a specified current distribution. An example problem illustrates the optimization of a section of a bus network containing a fork, with the imposed limitation of achieving a specified uniformity in the current. In cases where the current in the individual conductors may vary, Kelvin's law does not apply. Further extension of the technique to a full pot set of conductors poses additional problems which are discussed, but whose solution has not yet been accomplished. Aluminium 2006 45th Annual Conference of Metallurgists ofCIM Montreal, Quebec, Canada Edited by

Jan 1, 2006

By Doug Halbe

?Many are called, but few are chosen.? The biblical adage applies not only to life, but also to hydrometallurgical processes. There have been, in the past, many outstanding successes with new processes ? and also some dismal failures. What are the odds of success for a new process? When there have been problems, why? What can you do to make sure these problems don?t occur with your process? What effect will a slow startup have on project economics? How do financial institutions ? the people who loan your company money for the project ? feel about new processes and why? Is it possible to predict or estimate the time required to reach design parameters?and if so, how do you sell this estimate to management ? and financial institutions? Probably most important ? when do you start thinking about the answers to these questions?

Jan 1, 2003

By Jason N. Scott

CFA piling is a ?blind? construction process that relies heavily on the rig instrumentation to produce sound piles. If the data measured and recorded during construction can be made available to engineers and managers within hours after construction then there are many economic and quality control benefits that can be realised. A state of the art CFA instrumentation and data management process has been developed in the UK. The key components of the instrumentation, GSM data service and the central database are described. Many benefits to the business have been realised and, where possible, these are quantified.

Jan 1, 2006

By F. Alsobrook

Industrial minerals are receiving increased attention by metals, coal and other companies seeking to diversify and stabilize earnings. Each industrial mineral has a unique set (and sub-sets) of business dynamics, however, and the diversity can present a bewildering maze to the corporate planner. Shrugging off this complexity and relying on serendipity for entry opportunities often results in unsuitable acquisitions. An effective alternative used in exploration can also be applied to strategic planning. By providing focus and direction, this flexible methodology can prevent wasting corporate resources on random pursuits and result in a quicker, more satisfactory achievement of diversification goals.

Jan 1, 1990

By O. A. Bascur

It is difficult to analyse the economics without an integrated view of mine transactions, stockpile inventories, process flows and assays. The lack of integration of mining and metallurgical information with sufficient detail to analyse and act is a problem. However, to take action requires real time information from manufacturing assets, corrected for gross errors from trucks, shovels, conveyors, faulty sensors, bad instrument calibration. Validation methods use process models to identify inconsistent information in the case of corrupt actionable information. This paper presents new strategies that transform the data into business information for continuous improvement and optimization. This technical presentation will review recent implementations enabling large metallurgical complexes to improve their data quality for overall production and energy management. A competence center emerges as an enabler for implementing operational intelligence. The evolution of Web services to troubleshoot plant information and to collaborate at the enterprise level is presented.

Jan 1, 2014

By M. Bunch

"THE SUPER CYCLE IS GONE The utopia of the rising sales volume, for mining companies from 2002-2011, was entirely due to rising production volume and prices. The Australian mining sector experienced an 18 percent annual growth rate in revenues, and 11 percent growth in prices. (1) However, EBIT remained flat during the same time period. In addition, Australian mines saw a 7 percent annual decline in both labor and capital productivity. (2) Mines in the U.S. and Canada produced similar results, whereas the world-wide mining industry has seen a productivity drop of 40% since 2001. (3) The decade “Bull Run” of rising prices was trashed by companies that chased low-quality assets while increasing debt on their balance sheet. It seemed everyone believed the “super cycle” would last forever, while completely ignoring the history of cycle downturns. Worldwide mining operations are as much as 28 percent less productive today than a decade ago, according to new McKinsey research. The results from McKinsey’s new MineLens Productivity Index (MPI), which adjusts for declining ore grades and mine cost inflation, show that the pronounced decline in productivity is evident across different commodities and is seen in most mining players and geographies. (4) McKinsey sees three important areas of focus to address the root causes of productivity decline. 1) Embed effective management operating systems at mines 2) Prioritized operational excellence and capabilities development 3) Focus on innovation Reality has now settled back in and companies are struggling to make ends meet. The basic management staple of controlling costs and improving the production/productivity that was lost in the excitement is now back in play. Traditional cost-cutting approaches, such as across-the-board spending cuts, layoffs, and hiring freezes are only short-term initiatives and will not permanently improve a company’s cost structure or improve long- term competitiveness. This can only be accomplished by engaging front-line employees and empowering them to make necessary improvements in their daily work. It is time for leaders to lead and develop cultures of continuous improvement within their organizations in order to sustain their mining project to the end of mine life. Successful operating managers require two different skill sets of Leadership and Management; knowing how to lead people in their organization and how to manage the work they do."

Jan 1, 2016

By Roger Davieds

FACT: a company?s profitability (or loss) is directly related to the efficiency and effectiveness of its maintenance operation. Fact: in order to contribute in a positive manner, maintenance must understand what its true purpose is in the organization. It is easy to say our main purpose is to increase: ?equipment uptime ?OEE ?asset life cycle We all understand this; so does management.

May 1, 2010

By G Campbell-Cowan

Much has been written about the fact that most transformation efforts disappoint. This paper addresses factors that should be taken into consideration in planning and implementing transformation programs to ensure success.In 2009, St Barbara commenced a transformation program to address issues of chronic poor quarterly operational performance; financial pressure caused by the unreliable operational performance; and an inability to develop business plans with integrity and to reliably deliver on the plans. As a result of a number of years of disappointing operational performance, St BarbaraÆs culture was not conducive to business success.This paper uses lessons learnt during St BarbaraÆs transformation program to highlight key characteristics of change programs that can generate significant sustainable benefits. While there were many benefits from the transformation program, the most significant impacts of St BarbaraÆs program have been transformation of the companyÆs culture and capability of people as business leaders; the establishment of a business systems framework to guide the design and development of systems; and developing support functions, for example centralised procurement and supply chain, business improvement and technical services.CITATION:Campbell-Cowan, G, 2012. Business transformation - Lessons learnt for successful change, in Proceedings International Mine Management 2012, pp 135-142 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 20, 2012

"Butte originated as a placer mining camp. The first gold discovery was made in the year 1864, near what is now Main Street. Placer mining was vigorously prosecuted along Silver Bow Creek and in Missoula, Buffalo, Town and Parrot gulches for a period of five years, at the end of which time, in 1870, the camp was practically deserted. In the meantime, the quartz veins so prominently traceable over the hillsides were located, the first location being made by W. L. Farlin and called the Black Chief claim, and later restaked as the Travona. Reasoning from the presence of the gold placers, free-milling gold ores were eagerly looked for by the early prospectors. Claims covering the great Rainbow and other silver lodes were located in the sixties. The presence of valuable silver ores in these veins caused the staking out of many claims, believed to be valuable only for silver, but which later proved to be enormous copper producers.Treatment of these early discovered rich ores was first attempted in arrastres. Later, stamp mills were built. The Centennial dropping 10 stamps, was the first, and in 1875 Mr. Farlin built the Dexter 10-stamp mill, intro¬ducing chloridizing-roasting. More successful processes were soon introduced and several large mills built, among which were the Alice, Lexington, Silver Bow, Moulton and Bluebird, in all representing a total of 290 stamps. The silver mining industry reached its zenith in 1887 and declined rapidly in the early nineties, following the sudden drop in the price of silver in 1892.During this period of silver mining activity the business of copper mining was making rapid strides. Development of the veins, located as silver veins, had uncovered copper ore in many instances. There was great activity in ""claim staking'' in the years from 1871 to 1879, during which period most of the claims covering the present productive copper area were located."

Jan 1, 1913

By Frank A. Linforth

The object of this paper is to present a brief outline of the methods of geologic mapping employed in the Geological Department of the Anaconda Copper Mining Co., at Butte, and to show by means of a few typical examples the practical nature of the results obtained. The extremely complicated geological conditions early encountered in Butte mining led mine operators to realize the necessity of accurate detailed geologic mapping m an aid to successful development of the ore bodies. The organization of the Anaconda Geological Department was undertaken in 1900 by H. V. Winchell, who, in conjunction with D. W. Brunton, worked out the essential methods of procedure which are, in the main, followed at the present time. Since the year 1906 the geologic work has been under the direction of Reno H. Sales, and in some respects the scope of the work has been slightly enlarged. An excellent article describing the general equipment of the geological department was presented by D. W. Brunton at the British Columbia meeting of the Institute in 1905.' His idea, that data collected underground and recorded should be put to practical use and not remain a mere " inventory of the company's underground possessions," is the keynote to the success of applied geology in Butte. The geologic notes are taken as soon as possible after the ground is broken so that any mistake in the mining may be corrected at once, or any particularly advantageous procedure may be suggested before any useless work is done. Taking the notes underground is a comparatively simple matter, but a few necessary precautions may be pointed out. The essential to success is that the notes shall show exactly what geological facts are disclosed. The observer must discriminate carefully between important and unimportant exposures in making the record, especially as regards the relation between veins and stringers, between faults and minor slips, or between the characteristics of veins of different ages. A simple color scheme has been adopted for making this record. Red pencils are used to indicate

Jan 1, 1914

By Henry Sturgis Drinker, Rossiter W. Raymond

Jan 1, 1914

By Ralph Hayden

PAGE I. IntRoduction........239 II. Definition of Anaconda SLime....240 III. The Source of Slime......240 Remodeled Flow Sheet......240 Old Plow Sheet,.......242 IV. ConStitution of Slimes......243 Chemical........243 Physical.........243 V. The Slime Problem.......247 VI. THe Experimental Slime Plant....248 VII. Slime Thickeners. ETc .......249 Slime Ponds........249 Tanks.........249 Comparative Efficiency of Open and Baffle Tanks .260 Callow Tanks........252 Kuchs-Laist Centrifugal Separator....253 Garred Filter........256 Dorr Continuous Thickener.....256 VIII. Concentrators........257 Round Table........558 Peck Centrifugal Concentrator....259 Competitive Tests.......260 Twenty-Deck Round Table..... 260 Slime Feed Distributor......261 IX. ConcluSion.........262 I. Introduction. In the wet concentration of ores there is always a certain amount of very fine material with which to contend. and which invariably carries such quantities of value that the treatment of it is worth while. commercially. This fine material usually contains that portion of the ore which hinders the separation of the mineral values: namely. the colloidal material resulting from the decomposition of certain constituents of the ore. The object of this paper is to show what efforts have been made to solve the slime problem as it occurs in the concentrator of the Washoe

Jan 1, 1914

By H. T. Van Ells

The following is a brief description of the cost accounts in effect at the mines of the Anaconda Copper Mining Co. The accompanying chart, Table I., shows the distribution of labor, materials, and redistributable accounts to the various operating and repair accounts. OperatiNG. Development. Owing to the fact that every mine has its peculiarities in formation and methods, the question of arriving at what charges should be included under the head of " Development" is one that has occasioned considerable thought and comment, and in the cost sheet of the Anaconda Copper Mining Co. this account has been sub-divided to show the expenses of breaking ground, tramming, timbering, shaft sinking, up-raising, and cutting stations and skip chutes. It has always been the policy of the company to charge the entire cost of this work to operations monthly, whether the mines are producing or not, also the cost of the opening up of new mines; and only surface construction and additions are charged to capital, excepting original machinery installed for operating pumping plants. Explanations of the charges to the various sub-accounts follow : Breaking Ground.—Work performed in driving cross-cuts from the station, or cross-cuts from the drifts, and diamond-drill work, for the purpose of discovering or developing ore bodies. Tramming.—Cost of tramming waste produced by cross-cuts mentioned above. When waste is hoisted to another level to be used for filling, the charge to this account stops at the station, and when hoisted to surface the charge includes tramming from the collar of the shaft to the dump. Timbering.—Cost of timbering the cross-cuts mentioned above includes the cost of handling and framing such timbers, but does not include the wages of station tenders and top carmen.

Jan 1, 1914