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By G. F. Doggett

In describing accounting methods at Lake Shore Mines, it is the intention of the writer to limit the discussion to the principal features of the system used in securing cost figures and other statistics. The subject can be conveniently treated under the following divisions: (1) Time-keeping and Labour Distribution (2) Supplies: Handling and Distribution (3) Method of Assembling Data for Cost Purposes (4) Details of Operating Costs Time-Keeping and Labour Distribution After a new employee has gone through the routine of being 'hired on', he is assigned an employment number corresponding with the group applying to his occupation. This is for identification purposes in the plant and time office. He is also given an individual serial number, the use of which will be refer-red to later. On entering and leaving the plant, each employee passes through the clock room adjoining the time office, where he registers the time in and out on time recorders, on the clock card (Figure 1) bearing his name and number. It is the duty each morning of the time clerk to extend the hours worked by each employee, as indicated by the clock for the previous day, and at the end of the half-month period the total hours are multiplied by the rate and entered in the space provided for total wages at the bottom of the card.

Jan 1, 1935

By C. S. Ek

As a continuation of previous work, further tests have been carried out to recover silver from the residues obtained in a zinc jarosite process. Selective flotation has been performed with different reagents, and ?cleaning steps have been introduced to upgrade the silver concentrate. Leaching of crude residues, as well as flotation tailings, has been carried out with cyanide and thiourea. Finally, the different beneficiation methods are compared, and the industrial aspects? of their application are reviewed.

Jan 1, 1990

By Ralph H. Light

The recent surge in demand for uranium in the United States, accompanied by a significant increase in price, has resulted in exploration, mining, and milling of lower grade ores than have been exploited in the past. To sustain production levels of uranium with lower grades of feed requires larger tonnage mill operations. Also, because of recent environmental regulations, mill operations must be prepared to properly contain large tonnages of tailings, and recycle, treat and discharge, or evaporate mill effluents. Thus, the advent of lower grade ores, larger tonnage mills, and environmental considerations has made the cost of milling a critical factor in today's uranium production economics in the United States. Three basic milling methods are employed for extracting uranium from ores: 1. Acid leach, countercurrent decantation, and solvent extraction. 2. Acid leach, resin-in-pulp, and Eluex. 3. Alkaline leach, solid-liquor separation, and precipitation. Vanadium often occurs as a valuable by-product in ore deposits located in the Uravan mineral belt in Western Colorado. Also, lesser amounts of vanadium may occur in ores from South Dakota, New Mexico, and Utah. Vanadium is usually extracted in the acid leach solution with uranium and recovered by solvent extraction after recovery of the uranium. By-product recovery of uranium from phosphoric acid and porphyry copper dump leach solutions is now receiving considerable attention. Pilot plant studies are under way and construction of commercial plants is in progress.

Jan 1, 1977

By S. E. Jackson, L. J. Cabri

Quantitative determination of gold at sub-ppm concentrations in sulphide minerals is an important component of deportment studies for sulphide-gold deposits. Laser Ablation Inductively Coupled Mass Spectrometry (LA-ICP-MS) analysis is preferred for this application because it rapidly and cost-effectively provides spatially resolved (<20 pm), low ppb concentration data for gold and other elements in mineral grains. Recent advances in LA-ICP-MS analysis include the development and application of elemental mapping. Raw signals from multiple line scans or lines-of-spots are deconvoluted and calibrated to generate elemental maps which provide detailed information on spatial variations of gold and other elements within and between grains.

Jan 1, 2011

By A. J. Richins, M. G. Nelson, R. Dunne

From the inception of flotation in the late 1800s, coarse particle recovery has been a challenge to practitioners. By the early 1900s, flotation processes included oil flotation, skin flotation, agglomeration flotation, and froth flotation, and for each there was a proliferation of flotation equipment. Ensuring good coarse particle recovery included desliming of the feed and proper conditioning were required. Froth flotation was at first used mainly to treat finer materials from grinding circuits. The maximum size for coarse particles was from 3.18 to 4.78 mm. In froth flotation, large particles with high specific gravity tend not to be recovered. Coal and minerals of low specific gravity and flaky minerals such as graphite, mica, and talc can be floated in larger sizes. In the early 1960s, the phosphate industry began using column cells to recover coarse particle by froth flotation, but early columns suffered from poor bubble generation and sanding at the flat base of the column. Recently, improved coarse particle recovery has been the object of new cell designs—the Eriez HydroFloat™, the Jord NovaCell™, the FLS coarseAir™ cell, and the Cidra P29 integrated system. The paper will follow the development of coarse particle flotation with a focus on the development, laboratory assessment, and operation of the new flotation equipment and technology designed to recover coarse particles.

Feb 22, 2026

By Youn-Bae Kang

In order to overcome weak points of steel for its engineering applications, in particular, for environmentally benign, energy-efficient, lightweight engineering systems, a number of new steels have been proposed, especially to improve strength-to-weight ratio (specific strength). Mass production of these steels, however, has encountered a serious roadblock particularly in the steel refining and casting processes. This is because their chemistries and cleanliness requirements are vastly different from those of the conventional steels, and thus an incremental improvement of the prevailing process technologies is found hard to meet the requirements. In this study, a new process is proposed, which employs inert gas bubbles in the shroud nozzle, liquid steel drops in the degassing chamber, and the siphon transport for continuous casting. The proposed process which integrates the final refining and cleaning steps prior to casting is expected to be a technologically disruptive innovation on the conventional counterpart. The effectiveness of the individual steps is discussed with experimental results.

By Don Stevens

The Denali Prospect (147° 08&apos; 20" W, 63° 08&apos; 50" N) is located on the south flank of the Alaska Range in the Clearwater Mountains in south central Alaska. (See Figure 1). The mineralization was discovered in 1963 and surface explora¬tion began the following summer. Surface trenching and diamond drilling were used to locate and sample the mineralized zones. In 1969, an adit totalling approximately 1400 feet was completed. In 1970, a -15% grade decline approximately 1800 feet long was completed. Further diamond drilling was done along with both underground programs. Although much work remains to be done to properly evaluate the prospect, results from all the work to date are quite encouraging. This paper will consider the geology of the prospect and the surrounding area, some- aspects of the geochemistry of the sulfides, and the origin of the sulfide deposits. This paper includes data from this writer&apos;s Ph. D. dissertation, "Geology and Geochemistry of the Denali Prospect, Clearwater Mountains Alaska" from the University of Alaska and subsequent work.

Jan 1, 1972

By C Adams

Reports of delays and cost blowouts in major study and construction projects are becoming increasingly prevalent in the resources industry. This is mainly being attributed to an escalating cost environment associated with the increased number of projects in the development to construction pipeline and a scarcity of competent skilled resources to deliver these projects. However, not all this effect can be directly attributed to the current environment. Historically the mining industry has not performed well in its ability to deliver projects according to the financial and physical parameters forecast in the feasibility study process. To manage the risks associated with delivery of major projects, resource companies need to ensure they use a standardised approach to management of their project development to satisfy project objectives and enable more efficient use of the increasingly limited available resources. Each discrete step in advancing the project from scoping study to operations needs to be integrated, reducing the amount of rework and duplication. This paper is primarily a consolidation of existing ideas on project management systems but also introduces new concepts to solve current issues. It describes the basic components of a typical mining project, the issues that commonly arise, the key attributes, and critical steps required for an effective integrated project management system covering projects from initial scoping studies through to project commissioning and operation. This paper focuses on technical study components of the mine development project with allowance for transitioning to design and construction and operation phases.

Jan 1, 2006

By Eric D. Monrad

Supply chain simulation modeling is taking on a more prominent role in mining project planning and decision making. Transportation costs for the supply chain can form a significant component of the overall cost to provide product to the end customer. In recent years, computing power has increased, simulation software has advanced, and simulation specialists have become even better equipped to provide sophisticated analysis and recommendations. This has led to a virtuous cycle of owners expecting and supporting data-driven analytics, which drives further advancement. This paper discusses developments in supply chain planning and two case studies from recent simulation modeling analyses.

May 1, 2013

"What can we do in ground engineering to reduce damage to the environment, to repair historic pollution, to reduce our demand on basic resources and to reduce the carbon footprint of our industry? Some developments in geotechnical engineering are already heading in the right direction. These include reductions of ground pollution from grouting, improved dewatering procedures and advances in mix-in-place processes, ground improvement and jet grouting.There is increased interest in certain promising technologies (for example, drilled partial or full displacement piles), but this approach remains for the moment somewhat avant-garde. These piles require substantially greater power to install, and the overall sustainability balance for general application has yet to be shown to be in their favour. They are particularly suited to polluted sites where the problem of dealing with spoil would be costly and where, in the past, driven cast in-situ piles would have been employed. Drilled displacement piles offer some environmental benefit over driven piles in that they cause far less drawdown of potentially contaminated near-surface ground into sensitive, underlying aquifers.There is also great interest in various means of increasing the frictional capacity of bored piles, both conventional auger and continuous flight auger (CFA) piles, by threading or ribbing the soil/pile interface. The increase in adhesion capacity allows reduction in the pile dimensions necessary for a specific load. This obviously leads to less construction waste, but also to less permanent material consumption in the piles and also in the pile caps.The role of ground improvement remains significant for brown land sites and lower capacity foundations. Information technology (IT) has improved the quality assurance of stone column construction, for example. From the sustainability point of view, this is a good news method; here is no cement, no pollution and little obstruction to future redevelopment. We now need to introduce recycled crushed materials instead of natural aggregate as general practice and the technique’s green credentials will be really compelling."

Jan 1, 2009

By W. E. Cassan, W. L. Eaton, James Westfield, W. M. Romisher, Karl Hughes, S. H. Ash

"INTRODUCTION Funds were made available to the Bureau of Mines, United States Department of the Interior, for anthracite investigations during the fiscal year ended June 30, 1945. One of the approved projects was to conduct inquiries and scientific and technologic investigations having a bearing on the anthradite mine-flood problem. The investigative work done from July 1,1944, to June 30, 1946, is described in previous reports (5, 8, 10, 24, 28). 6/Purpose of Report The purpose of this report is to describe the investigative work conucted by the Anthracite Food-Prevention Section, Safety Branch, Bureau of Mines, during the period July 1, 1946, to June 30, 1947,Scope of WorkInvestigative work during the fiscal year ended June 30, 1947, was conducted under the direction of D. Harrington, chief, Health and Safety Division, and S. H. Ash, chief, Safety Branch, Bureau of Mines, Washington, D. C.The broad objective of the investigative work was to obtain factual day on: 1. Anthracite reserves of Pennsylvania.2. Underground water pools.3. Barrier pillars.4. The ""buried valley"" of the Susquehanna River.5. Infiltration of surface water into underground mine workings.The above-mentioned investigations are being continued during the fiscal year July 1, 1947, to Juno 30, 1948.In addition to the investigative work covered in this report, Ash end Eaton presented a paper on barrier pillars, which proposes a method for designing barrier pillars and has been Published by the American Institute of Mining and Metallurgical Engineers (5);"

Apr 1, 1948

By D van der Spuy, T Kewe, K Keet, N Moffatt, A P. Paine

The Blue Cube Mineral Quantifier Inline (MQi) instrument uses reflective light spectroscopy and advanced chemometrics to measure mineral or elemental grade in a slurry line. The instrument takes scans continuously and sends data to the DCS or PLC control system.Controlling the concentrate grades on a flotation circuit using low-frequency measurements can be difficult or impossible, especially on a circuit that has fast process dynamics. The ability to rapidly measure changes in grade makes it possible to continuously manipulate the flotation circuit operating parameters such as level, airflow and reagent addition set points to optimise plant performance throughout changing conditions.At Barrick’s Porgera mine in Papua New Guinea the flotation circuit feeds sulfide concentrate slurry to a pressure oxidation circuit. In order to maximise gold recovery in the flotation plant and increase performance in the pressure oxidation process, there is a stringent requirement to maintain a stable and optimum sulfur grade. The gold recovery is directly affected by the sulfur grade as most of the gold at Porgera is submicroscopic and associated with the sulfides (disseminated?pyrite).Porgera considered various points in the flotation circuit for installing Blue Cube analysers. This was part of a plant upgrade to improve process control. Due to budget constraints it was decided to initially only install one Blue Cube analyser on the final concentrate stream of the flotation circuit measuring sulfur, sulfides, gold and particle size. The accuracy of the calibration results were very good for all these properties. The sulfur measurement was used in an advanced control system to optimise and stabilise the grade. The paper presents comparisons between mineral grades determined using analytical laboratory analyses and the online Blue Cube data measurements, as well as benefits achieved by measuring grade online. An analysis of the plant data before and after installation of the Blue Cube and the advanced process control upgrade indicate that the flotation recovery increased by 1.98 per cent.CITATION:Kewe, T, Moffatt, N, Strobos, P, van der Spuy, D, Paine, A P and Keet, K, 2014. Evaluation of the Blue Cube MQi slurry analyser for application in an advanced control system for the optimisation of a gold sulfide flotation circuit, in Proceedings 12th AusIMM Mill Operators’ Conference 2014 , pp 357–362 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 1, 2014

By S. Torno

The elimination of ultrafine (<10 µm) clay particles is essential to the treatment of abandoned coal-washing plant tailings for the recovery of the remaining coal fraction by enhanced gravity processing. Effective hydrocyclone classification is required to remove this fraction. The highly variable composition and particle size distribution of such wastes creates significant difficulties in the operation of hydrocyclones for such classifications. Hydrocyclone laboratory investigations and their plant setup require lengthy or time-consuming tests. The use of empirical models of such classifications frequently requires modification to correspond to actual operating conditions. Results of the evaluation of computational fluid dynamics (CFD) modeling to predict hydrocyclone classification of coal-washing plant tailings are presented. Results of the standard k-epsilon turbulence, SSG turbulence and large eddy simulation CFD models are compared with the results obtained from analyzed hydrocyclone classifications. The CFD models tested are shown to be very effective in the simulation of hydrocyclone classifications for the determination of the classification particle size and adequate for determining the efficiency index values for many applications. The large eddy simulation model was identified as the most precise, but it is recommended that all three models be improved simulations of classifications above and below the classification particle size.

Jan 1, 2011

By R. I. Jeffery, J. W. Summers

An account is given of the verification and calibration of a numerical modelling technique that has been developed for the prediction of subsurface strata deformation following the extraction of coal by longwall mining methods.

Jan 4, 1992

By G Tsatouhas, R Newell, K Y. Wong

A sulfide ion selective electrode was used to control sulfidiser addition in the flotation testing of a synthetic and a naturally occurring ore containing malachite in order to compare the behaviour of sodium sulfide and calcium polysulfide. Both slug and controlled potential sulfidisation methods of addition were used. Under defined optimum CPS conditions, calcium polysulfide was a more effective sulfidising agent than sodium sulfide on the basis of both capital and operating costs. Surface and solution studies were used to compare the mechanism of each sulfidiser. For calcium polysulfide, XPS showed that polysulfide ions are adsorbed, whereas for sodium sulfide it is the hydrosulfide ions that are adsorbed on the mineral surface. For calcium polysulfide, the CuSx layer was believed to form on the malachite surface, which promoted the flotation of the malachite, by xanthate. Studies of surface morphology of the sulfidised malachite showed that a fairly uniform sulfidised layer is formed with both reagents. The use of sodium sulfide resulted in a thinner initial sulfidised layer compared to polysulfide at equivalent initial sulfur concentration.

Jan 1, 2005

By Frank J. Arland

Augered-Cast-in-Place piles have been used successfully for many deep foundation applications. The four case studies discussed herein describe ACIP pile projects where problems developed during ACIP pile installation requiring changes to the method or sequence of installation. The case studies illustrate the importance of understanding existing subsurface conditions and project constraints when considering the use of this pile type. Ground loosening and over-excavation of soil during the augering process, a significant concern for fine to medium sands and non-plastic silts below the water table, can significantly impact adjacent structures. This risk needs to be evaluated during the pile selection process and generally can be mitigated, but not eliminated, by requiring the use of piling equipment with high torque and slow auger rotation speed to advance the auger with minimum amount of rotation. In some applications where high lateral stresses in the soil are present such as at the base of retaining structures, the use of ACIP piles may not be appropriate if structure movement is unacceptable. On the other hand, ACIP piles have been successfully used to support deep foundations in preconsolidated varved deposits where the new structure was designed to accommodate recompression settlement.

Jan 1, 2004

By Peter Grandone, Ludwig Schmict

The injection of oil-field brimJs into subsurface formations containing mineralized water ·now is .recognizud as the most satisfactory and effective means of disposal in Kansas.· Other disposal ·methods, such as impounding brines in evapOTation nonds and controlled diversion into surface streams, have not prov-ed entirely successful, principally. because the volumes of brine to be disposed of were large, the soil f;?xtr~~mely porous, the net evaporation is low, and the rairiiall insufficient fc)r adequati.:~ dilution of the brine. The disposal of brine by subsurfaCE) inj'ection is often: more. expensive than by either of the above surface methods; nevertheless, surface dis:pos?,l ow.ing to the damaging effe-c.ts of· salt water to plant, animal and aquatic life and to potable water supplies has been:a long-continuing problem with many technical, economic, and 'legal·complexiti,2s

Aug 1, 1943

By T J. Grandfield

Paste fill has been used successfully at Henty Gold Mine for the past five years. It has allowed 100 per cent extraction of the orebody, stabilised poor ground and enabled wide sections and offsets to be mined safely. However, there are a number of inefficiencies in the current paste fill system. These include the low output from the drum filter, the addition of aggregate to the paste to compensate and the trucking of paste from the plant to the portal. These inefficiencies have increased the operating cost of the paste fill system and caused a number of operational challenges such as blockages and increased pipe wear. These challenges have been partly overcome by taking ownership of the paste fill process, improved quality control and better communication. Henty is currently developing two new orebodies, the Mt Julia and the Darwin and has an opportunity to build an efficient paste fill operation. This is likely to be a high density paste system without aggregate, either located above the new orebodies or located at the plant and pumped to the new site.

Jan 1, 2002

By Vladimir Adamek

This paper describes the Bureau of Mines development of a novel subsidence prediction methodology suitable to the mining and geologic conditions in the Northern Appalachian Coal Region. It describes the computation of vertical and horizontal movements, inclination, curvature, and horizontal strains. The substance of this method is the separation of the effects of lithology by introducing a correlation between hypothetically homogeneous overburden and existing lithologic conditions, while providing for different mining conditions, i.e., underground geometry and overburden thickness. The effects of lithology have been expressed in the form of a variable subsidence coefficient within the subsidence trough. The subsidence co-efficient is considered a constant for other predictive methods. Field data from 16 test sites at 11 Bureau longwall panel studies were used in the analysis. For each panel, the characteristics of the variability of the subsidence coefficient were defined. Regression analysis of the subsidence coefficients from all test sites on their locations relative to the edges of their respective panels yielded a third-degree polynomial equation. The results from additional longwall panel studies, not included in the regression analysis, were used to prove the validity of this method. To facilitate the use of this precalculatlon methodology, a computer program was written in BASIC for use on a personal computer.

Jan 1, 1987

By P. S. Haury

"INTRODUCTION Preliminary examinations of the Mohawk zinc prospect were made by John 14. Price and the author in July, August, and September 1943. Considerable quantities of oxidized lead and zinc minerals were found in old shallow work¬ings along two faults - one an over thrust fault with Paleozoic limestone in the hanging wall overlying Cretaceous shale and arkose in the footwall of the fault, and the other a bedding fault in the Paleozoic limestone.The chances appeared good for finding important lead-zinc sulfide ore bodies at 200 to 300 feet beneath the surface, so exploration in three steps by the Bureau was recommended:Surveying, mapping, and character sampling of the outcrops with topographic and geologic mapping of the immediately surrounding area.Preliminary drilling of four test holes, aggregating about 1,500 feet, to locate the top of a possible sulfide ore zone and determine the thickness and intensity of the sulfide mineralization.Contingent upon favorable results of the second step, diamond drilling of about 6,300 feet of additional hole to explore the sulfide ore bodies.The outcrops were surveyed and sampled, a topographic map was made of the area, and the geology was mapped. A project was set up for preliminary drilling of step 2 in the fiscal year 1944-45. An access road to the drill sites was built in April 1945. Diamond drilling was started on April 28 and completed on September 25, 1945, under the supervision or the Bureau of Mines. The exploratory work is covered in this report."

Oct 1, 1946