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By W. F. Faragher, W. A. HORNE

Previous interrogation of German scientific personnel by numerous in- vestigators and the examination of evacuated documents indicated that fur- ther information was desirable on a miscellany of products and processes of interest to the Petroleum Industry. Accordingly, Dr. Pier and a large number of other men of the I.G. Farbenindustrie, A.G. plant at Ludwigshafen/ Oppau were further interrogated in July-1945. The information contained in this report supplements that previously reported in the CIOS report of 16 August, 1945: "Report on Investigations by Fuels and Lubricants Teams at the I. G. Farbenindustrie A.G. works at Ludwigshafen and Oppau", edited by Lt. Col. R. Holroyd, (FP).

Aug 1, 1943

By Henry S. Drinker

(Canal Zone Meeting, November, 1910.) FEW men reach middle life without having had the experience of failure in one or more undertakings; and most of us can look back with gratitude to help or advice given us by friends at critical periods of our lives. If, as men, we ask and take the benefit of such aid, why should we expect our sons to be stronger? A parent can make no greater mistake than to send a boy, however steady and intelligent he may be, off' to school or college, and expect the boy always to cope successfully with all the new conditions and new difficulties that may confront him. This is undoubtedly more the case with a freshman, in his first year at college, than in later years, or than it is with a boy at day- or boarding-school, where the boy receives a greater degree of care and oversight than can be given to the young man entering college; of all periods in life, the youth in his freshman year-fresh from the overshadowing care of home and school-may need judicious advice and timely aid. The change from the restraint of home and school to the freedom of college life is sudden and marked, and it is in this the first year of the boy or young man of 17, 18, or 19 years of age, that some tactful, judicious aid should be near him in his work and course. Some boys go to college so well prepared that they become careless and finally fall behind in their work from over-confidence. Others meet trouble from ambitiously trying to do more than their previous preparation, or physical or mental strength, can sustain. Others fall behind from illness-from injuries-from natural inability to grasp at first, without more aid than comes to them in the regular course of instruction, the higher mathematics-or mayhap the modern languages, or other subjects presented by the advanced curriculum of the present day. When a boy or youth begins to

Jan 1, 1911

By R. T. Swindeman

"INTRODUCTION This paper will discuss the topics in the recently released Conveyor Equipment Manufacturers Association’s (CEMA) Belt Conveyors for Bulk Materials, 7th edition, that deal with safety and maintenance. The most effective way to improve conveyor safety is through designing out hazards in the earliest stages of a project. When the safest way to perform maintenance is also the easiest, mechanics will naturally take the obvious and least hazardous approach. IMPORTANCE OF ACCESS Studies have shown that mechanics spend almost one-third of their time accessing the components to be serviced and approximately 25% of all fatal conveyor accidents occur during maintenance1. Chapter 2 of Belt Conveyors for Bulk Materials deals with design considerations. In Chapter 2 there are recommendations for access at the various sections of a typical conveyor for cleaning, inspection and maintenance. While, in some cases, providing access will increase the cost of the conveyor system there can be significant paybacks in reduced injuries, faster maintenance and easier cleaning. Piping and Conduit One of the significant recommendations in Chapter 2 for access is to restrict the mounting of piping and conduit to the conveyor structure in the Loading and Discharge zones of a conveyor. Piping and conduit are more permanent fixtures than maintainable components and should be located out of the way of components needing frequent maintenance. If electricians and pipe fitters are given convenient locations to make their runs they will natural use them. Flexible conduit and hoses can be used to connect to components from pipe racks and cable trays which further enhances maintenance. Access for Cleaning Another critical aspect of access is for cleaning. Approximately 33% of all fatal conveyor accidents occur while cleaning spillage and carryback under and around conveyors2. In the loading zone having sufficient height under the conveyor for cleaning increases the cleaning interval and allows for safer cleaning. In the discharge zone having adequate access for belt cleaning installation has a direct effect on the ability to install a proper cleaning system and perform maintenance."

Jan 1, 2015

By David Mast, Irwan Halim, Brian Hagan, Kaveh Talebi, Jason Edberg, Amanda Foote

On June 14, 2023 Jay Dee Contractors’ Tunnel Boring Machine (TBM) “Phoenix” holed through and completed mining the second drive of the I-75 Segment 3 Storage and Drainage Tunnel. Completion of the tunnel came only after overcoming several challenges, including a groundwater intrusion event which deposited thousands of cubic yards of wet ground material into the tunnel. This paper will discuss the events which delayed completion of the tunnel by over nine months, the risk management and construction approaches assumed by the Design-Build team during bid, several challenges faced by Design-Build teams when building stormwater resilience tunnels using traditional Department of Transportation standards, and recommendations for improving risk allocation and proposal documents for future similar Design-Build tunnel projects.

Jun 23, 2024

By R MacGillivray

The Golden Cross mine was an open-pit and underground gold and silver operation from December 1991 to April 1998. Closure of the mine has been based on an approach agreed among stakeholders. The initial phase was the release of a closure plan which was regarded as the blueprint for the following phases and the closure works required to implement the plan. The second phase involved lodgment of consent applications and their granting for the final water management configuration. The final phase is monitoring, confirmation that the site is performing as required by the closure plan and consents and settlement of final ownership, management and surety arrangements. Industry best practice modelling techniques have been used to finalise closure design and have been shown to be good predictors of site water management and discharge performance. Site discharges are in compliance with toxicology based water quality criteria for the protection of aquatic life and most discharges from the site, including those from the closed cyanide-tailings facility, can now be discharged without further active intervention or treatment.

Jan 1, 2002

By P. E. Venteer

The Grootegeluk coal-processing plant treats 3 kt of raw coal per hour to produce a middlings fuel coal and a coking coal fraction with ash contents of 35 and 10 per cent respectively. The plus 0,5 mm fraction is treated by heavy-medium processes, the final top size of the coal being 15 mm. About 400 t of minus 0,5 mm coal per hour is subjected to froth flotation. The routes originally considered for the processing of this fine coal were froth flotation, shaking tables, heavy-medium cyclones, and water only cyclones in combination with froth flotation. The results from tests on the fines arising from a small-trial open-cast mine are discussed. When the froth flotation route was decided upon, further tests were conducted on the selection of the equipment most suited to the particular requirements of this coal and the rest of the plant. Tests using different types of flotation cells and dewatering equipment are discussed. During the commissioning, several operational problems were encountered, and the work done to find the best solutions is discussed.

Jan 1, 1984

By D. Goodings, W. L. Fourney, Bonenberger, R., Uli Leiste

The Dynamics Effects Laboratory at the University of Maryland conducted a series of very small scale tests to measure the impulse delivered to a plate by the detonation of an explosive charge which was buried in saturated sand. These tests were conducted to support a full scale tests series being supported by the Navy (NSWC Indian Head Division) to learn more about loads applied to structures by explosive detonation. For each of the tests being predicted, a series of three tests were conducted at Maryland, one with a 0.203 gm charge, one with a .609 gm charge, and one with a 3.3 gm charge. A high speed digital camera (500 frames per second) was used to record the displacement of the plate as a function of time. From this the initial velocity of the plate was determined and then the impulse delivered to the plate by the explosive. A best fit line through the data was determined for the three model tests conducted and this equation was used to extrapolate the predicted impulse for the full scale tests.

Jan 1, 2005

By J. Preussner, U. Glatzel, R. Völkl, S. Prins, M. Wenderoth

Platinum base alloys are very corrosion resistant and have got a high melting point. Similar to Ni-base superalloys, which are used for jet turbines, the hardening effect of the intermetallic L12Pt3Al phase is used to receive a material that is creep resistant at high temperatures. Chromium is added to the alloy system to stabilize the L12phase down to room temperature. With the right amount of nickel the misfit and shape of the precipitates can be controlled. Various alloy compositions have been melted and analysed. With scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) a microstructure can be observed, which is very similar to the one in Ni-base superalloys. To support alloy development with simulations, a thermodynamic database of the Pt-Al-Cr-Ni system is about to be established. The SEM and EDS measurements provide useful input to the thermodynamic optimization. Also many data from the literature have been used to receive the best approximation. The Cr-Pt binary phase diagram has been reassessed and the latest results of thermodynamic modelling are presented.

Jan 1, 2006

By J. E. Murphy, L. A. Walters, F. H. Nehl, G. B. Atkinson

The US Bureau of Mines investigated the selective electrowinning of Ag and Au from cyanide solutions contaminated with Cu with the goal of decreasing the amount of Cu codeposited. Decreasing Cu codeposited will reduce refinery costs. Direct current was applied to the cell in pulsed and square wave voltages at 0.7 A h/150 mL of solution. Times tested for each cycle ranged from 1 to 10,000 msecs. Graphite, lead and stainless steel were evaluated as electrode materials. Square wave electrowinning at 70°C (158° F) gave the best separation of Ag and Au from Cu. Applying 2.5 V during the duty cycle, 0.0 V the rest of the period, a duty cycle of 10% to 30%, and a period of 100 msecs to 1000 msecs gave the following results: Ag concentrations decreased from 34 µg/mL to 0.1 µg/mL. Au concentrations decreased from 54 µg/mL to 0.2 µg/mL and Cu concentrations remained almost constant at 560 µg/mL.

Jan 1, 1995

Various factors influence the exploration geologist or geochemist in his choice of.an analytical method for gold and other elements which may help him find the elusive gold deposit. One of the first decisions the geologist must make is the nature of sample media to collect for his survey. Needless to say there are many media available depending on the situation. These include rocks, soils, heavy mineral concentrates (from overburden drilling and panned concentrates), humus, vegetation, water, lake bottom sediments, stream sediments, etc. The choice of the sample media will depend to a large degree on the state of development of the particular project from grassroots to mine feasibility. The nature of the geological information required will affect which media and which analytical technique should be chosen for the analysis. Valid sampling from the initial sample collection, preparation and subsampling aspects may also help to determine which analytical procedure is best. Cost and turnaround time are of prime. importance to the explorationist, as it should be, however, these aspects should not be detached from receiving accurate and reliable results.

Jan 1, 1987

"A growing public awareness of work-related diseases such as pneumoconiosis and the impact of this awareness on legislative bodies and on the skilled labour market are reasons why the Canadian mining industry must consider dust control of top-drawer importance. Measurements and standards related to the hazard are necessary to control a dust situation and to avoid excessive risk. The author discusses some of the methods of measurement, standards proposed and terminology used in this developing technology. The purpose primarily is to give a better understanding of the basic advances achieved by those who have applied current knowledge with a measure of success."

Jan 1, 1972

By C. N. Eze, C. K. Ezeh, O. Nnabuife, N. M. Ugwoju, S. C. Enemuor, V. Okechukwu

In this study, the efficacy of Providencia vermicola KUBT-1 in the leaching and beneficiation of Agbaja iron ore was evaluated under varying conditions of temperature, ore particle size, and pH. Agbaja iron ore is a Nigerian low-grade ore containing about 43%–52% iron and a high amount of gangue materials, including phosphorus (1.4%–2.0%) and sulphur (0.12%). The study was organised in triplicate in shake flasks with 48 samples. One millilitre of washed cells of Providencia vermicola KUBT-1 suspended in normal saline at 0.5 McFarland standard (108 cells ml-1) was introduced into each flask containing 50 g of sterilised ore in 100 ml of bioleaching medium, and the samples incubated at room temperature for eight weeks. The levels of upgraded iron, mobilised sulphur, and phosphorus were determined by atomic absorption and ultraviolet spectrophotometric analyses, respectively. Results showed that a particle size of 0.8 mm was optimal for iron upgrading and sulphur mobilisation while 1.0 mm ore size was optimal for phosphorus mobilisation. Up to 89.60% of the iron was upgraded while phosphorus and sulphur were mobilised, leaving residual values of 0.223% and 0.02%, in the ore, respectively. The organism produced best beneficiation results at a pH of 2.5 and a temperature of 3ºC. Correlation analysis with the Pearson’s correlation model showed a positive correlation between iron upgrading and sulphur-phosphorus removal (r =1.000, and r =0.967), respectively. These results present Providencia vermicola KUBT-1 as a promising candidate for large scale leaching and beneficiation of Agbaja iron ore.

Dec 15, 2025

By John Johnston

ONLY two of the Institute's 26 Local Sections were unrepresented at the delegates' three sessions, held on Monday morning and afternoon and Thursday afternoon of the annual meeting. The Philadelphia and Wyoming Sections alone sent no delegates. In all, seven hours were spent most profitably in reviewing the work done by the Institute at headquarters and in the field, comparing ideas and practices in varied activities, and in establishing personal contacts. Cordiality and the co¬operative spirit marked the meeting and apparently no one had any serious grievances to air. Four motions were introduced and unanimously passed. The first, which was introduced by B. L. Sackett, was a recommendation by the delegates that a national committee be appointed to cooperate with Local Sections in the matter of student activities, to promote Institute welfare. It was agreed that this recommendation be made simultaneously to the Board of Directors and to the Mineral Industry Education Division. A subsequent resolution by A. M. Smith was passed asking that a part of the duties of this committee be to secure the opinions of Local Sections as to the most desirable methods of interesting students in the preparation of technical papers, by giving prizes or otherwise, and to report their findings at the Section Delegates' meeting next year.

Jan 1, 1933

By J. F. T. Agapito, L. J. Gilbride

High horizontal stresses were recognized to impact roof stability more than 60 years ago. Since then, numerous measurements associated high horizontal stresses with difficult ground conditions. This paper presents case histories illustrating the practical usage of roof stress determinations for helping assess stability, not only in the case of high horizontal stresses but also of low stresses. Examples are given of high stresses associated with faults, mine design changes, quantification of stress shadow effect, and anistrophy. The paper concludes with a comparative evaluation on the effect of various stress fields on ground support requirements.

Jan 1, 2002

By Robert E. Brown

Magnesium recycling has been used to recover both new scrap and old scrap. It was used extensively in Germany during WWII to expand the magnesium supply. There were a large number of magnesium recyclers in the US who got their start smelting old scrap, old airplanes and old waste dumps from the WWII build up. As the world magnesium industry dwindled, only a few companies were left that did magnesium recycling as a primary business. The sand foundries tended to recycle of their production scrap in their melting furnaces. Even the original die casters tended to put scrap directly back into melting furnaces at the die casting machines. As high purity alloys were developed and the use of die castings in automotive work increased, the tendency was to let the magnesium recyclers convert the scrap back to high quality ingot. Automotive use has grown because of the low density of magnesium. This property is the one of the biggest problems to overcome in shipping scrap. Gates and runners from die casting are very irregular shapes and it is very hard to load a truck with enough material to get a low shipping cost per pound. Recent new equipment companies have developed magnesium equipment that is specifically designed to recycle, refine and cast secondary magnesium metal. These melt cells are supplied as integrated units to magnesium casting sites. The cost and effectiveness of this approach will be discussed.

Jan 1, 2000

The mining industry was one of the first industry groups to be confronted by and to respond to public and government pressure to improve its environmental management. Companies operating in New Zealand and the parts of Australia with firmer environmental and planning controls responded quickly with environmental staff appointments to their development and operating arms. Even in less demanding jurisdictions in Western Australia and Papua New Guinea environmental staff were added to the payrolls. The issues then and now were seen as pollution related with land and water housekeeping leading to progressive or eventual site rehabilitation. Increasingly, however, environmental issues are being recognised as being more complex. They are about equity and social justice. Pollution of water, air or land is seen by the public as a question of personal and public rights, more or less wherever the pollution takes place, on public or private land. Environmental issues in mining have become caught up in the global perspective and a more holistic approach to environmental management. Environmental issues touch every comer of the community and action is being demanded. Nowhere is this better illustrated than on Bougainville Island where increasingly militant demands by land- owners for redress for environmental degradation from the Panguna Mine, on close examination, revealed many years of disenchant- ment with the government and the mining company over a wide range of social, cultural and environmental issues. Failure to address this satisfactorily eventually led to a bloody rebellion and finally an act of secession.

Jan 1, 1991

By Michael A. Berdine

Twentymile Coal Company?s first longwall face in the late 1980?s was oriented approximately 45 degrees to the major coal cleats and 45 degrees to the primary horizontal stresses. This combination of stress and coal cleating resulted in frequent violent bursts of coal along the longwall face. The bursts created particles of sufficient size and force with the potential of causing injury to employees and occasional damage to shield components. Partial web cutting was subsequently developed in an attempt to relieve the stress on the coal face and required the shearing machine to travel to the tailgate and back for a full 36 inch web. The partial web cutting pattern is focused on first cutting the lower 90% of the seam to relieve the stress as the shearer travels from the headgate to the tailgate. The web depth during the headgate to tailgate pass is typically in the range of 70% to 80% and varies with conditions to maximize production rates. The top and bottom of the seam in the remaining 20 to 30% of the web are then cut out to allow the shields and face conveyor to advance. 100% of the web is cut at each gate end for a distance of approximately 19 shields. This paper addresses some general mine geology and the procedures and benefits of partial web cutting with respect to safety, production and maintenance on a high production longwall face.

Jan 1, 2004

By C. Twigge-Molecey

All projects that are implemented, have been given corporate go-ahead on the basis of a set of clearly defined targets. These are typically a production goal at a capital cost, operating cost and production schedule, that will yield an acceptable return on investment by the companies internal criteria. The challenge for the implementation team is two-fold, firstly to properly define the project criteria prior to board approval and secondly to deliver an operating facility that meets these objectives, in particular the ROI. The paper addresses the issues a project team and the company management must address for a successful project. Key questions that will be explored are: ? What is the status of key technologies? Are they well proven in commercial practice, completely novel or in between? ? Is the project schedule driven by market constraints or cash flow constraints? ? Are the risks of fast tracking worth the potential rewards? ? For a retrofit project, are all the technical and production interfaces and issues known at the time of approval to proceed? ? How much should be invested in technological development and engineering and at which phase? ? For an owner-operator, how much responsibility is it wise or appropriate to push down to vendors? The answers to these questions for a specific project will define how you go about a project, the resources required, the contracting strategies, the phasing and the appropriate level of investment in the definition and procurement phases, prior to starting major capital commitments and construction.

Jan 1, 1999

ON FEBRUARY 13, 1953 the Miami Copper Company signed a contract with the United States Government, through the Defense Materials Procurement Agency, whereby it under- took, with a base price of 27.359 per lb (subject to escalation based on wage scales and wholesale-price indices), to exploit a new ore body in its mine in Gila County, Arizona. Recoverable ore was estimated at 23,000,000 tons, averaging about 0.677 per cent copper. Moreover, the proportion of oxidized copper, difficult to recover by flotation concentrating, was so high that an average net recovery of only ten pounds per ton (0.5 per cent) was expected. The company proposed to mine the ore by the underground method known as undercut block-caving. Unfortunately the ore body, as has been true of all Miami's ore bodies, lay so deeply buried that no possibility existed of adopting opencut mining as has been done in recent years at Miami's neighbors, Ray and Inspiration. Probably the most distinctive characteristic of Miami's operations has been the extent to which it has developed and improved methods and equipment for underground mining. True, necessity was a potent stimulant, because its available ores since 1926 have been exceptionally low-grade; so, if the enterprise were to survive, it was necessary to keep costs at the minimum. This fact does not detract, however, in any way from the remarkable achievements of Miami engineers in conducting efficient and low-cost underground mining.

Jan 1, 1957

By Larry Powell

Rend Lake is an Army Corps of Engineers reservoir located in Franklin and Jefferson Counties in south-central Illinois. The lake consists of 20,000 acres of water and 19,000 acres of public access land. The site attracts over two million visitors a year and is surrounded by campgrounds and other recreational facilities. The lake overlies the largest tonnage of low sulfur coal in the state. Coal is being removed beneath the lake from five mines operated by three coal companies. Currently high extraction mining operations are approaching low-lying, environmentally sensitive, and high-use recreational areas. Advanced planning to maximize coal extraction and minimize potential effects of subsidence requires the development of procedures to assess the impact of high-extraction mining on the land use of the area. The Bureau of Mines, the Corps of Engineers, and the coal companies have initiated research to assess the following proposed planning steps to ensure the maximum recovery of the coal resources while minimizing impacts to surface land use: 1) Establish a dialogue between the surface and mineral owners; 2) develop a geographic information system to aid in assessing existing land use and potential changes; 3) assess the potential effects of subsidence on drainage, wildlife habitats, and changes in land use prior to mining; 4) coordinate the mining displacements with surface activities to minimize disruption; and 5) develop appropriate mitigation plans before mining occurs.

Jan 1, 1986