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By Glenn Mongillo

Discrete Element Method (DEM) software has been successfully used to simulate various machine/soil interactions and provide insight for industries such as mining and bulk material processing. This paper will investigate typical calibration techniques used in particle models for DEM simulation and physical calibration experiments with soft ground TBM cutting tools to incorporate parameters such as tool drag forces that contribute to required TBM torque. With a well calibrated DEM model, it is expected that TBM simulation results will be more meaningful and provide better insight into TBM performance, power requirements, cutting tool placement, and overall cutter head design.

Jun 13, 2021

By F. B. WEEKS

I HAVE chosen for my subject a mining district which in an article published four years ago I referred to in the following words: "One of the un- usual anomalies of mining development and history is that a district having added thirty or more millions of wealth to a principal mining state, situated within four to six miles of two transcontinental railways and two auto highways, and within 150 miles of the most widely advertised part of the United States, should have been so completely lost sight of that probably not one mining man in ten can tell offhand where it is situated." But this district never was a dead one: it was only slumbering. During the past four months, day by day, it has been emerging from that state of slumber.

Jan 1, 1929

By Greg R. Wheeler

Few members of the general public have a clear understanding of mineral resources. Most people do not know how minerals are mined or why they must be extracted from many diverse locations. Many people acquire knowledge of mineral development from mass media sources with incomplete details or obvious anti-mining bias. The California Mineral Education Foundation was formed in 1991 to provide educational opportunities for the public and industry. There have been major changes in earth science teaching requirements for kindergarten through 12th grade (K-12) curricula since the passage of California Senate Bill 813 in 1983. Model graduation standards, curriculum standards and the state science framework mandate substantial coverage of geoscience topics. The California State Commission on Teacher Credentialing has completed changes in multiple subject and single subject science credentials which will require more geoscience preparation for all teachers. The need for pre-service and in-service education in geoscience is at an all time high. Teachers must have continuing education to maintain their credentials and many are now seeking information in geoscience. The California Mineral Education Foundation designed and conducted the California Mineral Education Conferences held in August 1991 and 1992. The conferences involved lectures and field trips on mining geology, environmental problems and political concerns. Master teachers were employed to share how they get across mineral resource concepts in the classroom. Ninety-six percent of the participants stated that they had changed to a more positive perception of mining after taking the three day course.

Jan 1, 1995

By L. E. Porter

The demand for crude oil on the Pacific Coast during the year 1945. was so acute that the California crude supply had to be augmented by tank-car imports from the Texas and Rocky Mountain fields. Crude imports reached a high of 64,800 bbl. per day during June, with a total of 14,259,000 bbl. imported during the first 11 .months. The U. S. Navy also implemented the crude output from California pools by drilling and completing approximately 300 wells in the Naval Petroleum Reserve No. 1 (Elk Hills), from which an established production of 65,000. bbl. per day was reached in late February and maintained until Aug. 17, 1945, when it was reduced to its preprogram level of 15,000 bbl. per day. Even with the conclusion of the Pacific war on V-J day (Aug. 14), the military petroleum product requirements have permitted little material reduction in output of California crude to prewar rates. During the year, a total of 327-760,000 bbl. of crude was produced, or 19 per cent of the total crude production within the United States during the same period, as compared with 310,996,000 bbl. or 18.4 per cent of the nation's crude production in 1944.

Jan 1, 1946

By H. NORTON JOHNSON

THE oil industry in California during 1929 reached new heights and new depths in the discovery and development of the oil resources of the State. The discovery of new fields, and more especially the discovery and development of deeper prolific sands in known fields has, for the first time in its history, brought the potential production of completed wells within the State to over 1,000,000 bbl. oil per day. Constant improvement in equipment and technique has made possible economic development to depths unheard of but a few short years ago. Commercial production from a depth of over 4000 ft. was considered quite an accomplishment in 1923 when the Meyer sand at Santa Fe Springs was developed, and when later oil was successfully raised from this depth.

Jan 1, 1930

By E. A. H. Tays

At the present time, the mine-owner has a number of patent crushers to choose from, when contemplating the erection of a mill; and a number of new ones are yearly brought to notice. We all know that the stamp-mill is the old standard; but several of the patent crushers, especially of the roller-type, are not without their merits. Having had a working experience, extending over a period of four years, with the " Bryan roller quartz-mill," working alongside of stamp-batteries, I take pleasure in giving to the members of the Institute the benefit of my experience with this mill.*

Jan 1, 1900

By Robert Gorham Morse

This paper presents the results of an investigation made in the metallurgical laboratory of Columbia University, New York City. The object of the investigation was to determine how the tensile strength, the elastic limit, and the size of the grain, of a pure medium-carbon steel are affected by heating to successive temperatures between 500° and 1300° C., with slow cooling therefrom. Since Dr. Sorby's first investigations into the microstructure of steel, the study of the subject has been continued by Professor Martens, Mr. F. Osmond, Professor Arnold, Professor Howe, Mr. A. Sauveur, Mr. J. E. Stead, and many others. Among many valuable and interesting papers I mention the following as having a special bearing upon this investigation.* " Microstructure of Steel," by Albert Sauveur, Trans., xxii., 546 (1893); Microscopic Metallography," by F. Osmond, Trans., xxii., 243 (1893); "The Microstructure of Steel and the Current Theories of Hardening," by Albert Sauveur, Trans., xxvi., 863 (1896); "The Crystalline Structure of Iron and Steel," by John Edward Stead, J. Iron and Steel Inst., 1898. II.—Statement of Experiments. Through the kindness of Mr. N. Lilienberg, New York City, round rods 3/4 of an inch in diameter were obtained, which had been rolled from one ingot. The analysis of the steel was as follows : C, 0.343; Si, 0.027; Mn, 0.221; I?, 0.0266; S, 0.0037 per cent.

Jan 1, 1900

By H. O. Hofman

In the blast-furnace smelting of lead, copper and other non-ferrous metals, the largest part of the product obtained is slag. Its formation consumes more of the heat-energy of the fuel charged than any other chemical reaction that takes place. It is therefore of importance to know at what temperatures the different slags will form, so as to be able to choose in a given case the slag that will form at the right point in the operation, will keep the products thoroughly fluid, so as to insure a satisfactory separation, and will permit the consumption of fuel to be reduced to the lowest practicable point. While practical experience has brought out in a general way the leading differences as to the formation-temperatures of Rome silica—iron —lime slags, accurate details are still wanting. The object of the investigation here described was to supply some of these.* Prominent among the men who have worked on the fusibility of silicates are Lampadius, † Sefström,‡ Berthier,§

Jan 1, 1900

By James C. Sever

Two green field magnesium reduction plants are under consideration using dolomite as the raw material. The Calix calciner was independently selected for both plants. The unique design of this calciner is detailed and the advantages defined for the specific application. The low carbon foot print of this unit combined with the ability to capture food grade carbon dioxide makes this an environmentally proactive approach to carboniferous ore calcination.

Jan 1, 2015

By Q Liu, P D. Katsabanis

The energy output of crushed AN/FO, crushed AN/FO mixed with Aluminum (5%, 6.4% and 9.4% A1 by mass) and a commercial emulsion explosive has been measured using a detonation calorimeter. The charges had a diameter of 10 mm and were heavily confined by a 11 mm thick copper shell. In order to achieve stable detonation glass microballoons were used in the explosives so that the density of the AN/FO charges would be around 1.1 g/cc. The charges were detonated in vacuum and the detonation products were analyzed using gas chromatography. It was found that energy values were very close to calculated values obtained by ideal detonation codes.

Jan 1, 1993

By M. S. Celik

Adsorption of sodium dodecylsulfonate (SDS) and dodecylaminium hydrochloride (DAH) on Buller seam coal, New Zealand, have been studied. Both surfactants adsorb effectively on the coal below pH 8, and the adsorption isotherms established at pH 4 are essentially the same at lower concentrations. These findings suggest that the adsorption of these two ionic surfactants on coal is controlled by a hydrophobic bonding mechanism. However, the results of calorimetric studies suggest that coulombic attraction also plays a part in the adsorption mechanisms. It has also been found that both the SDS and DAH adsorbed in the first monolayer are not removed by lowering the surfactant concentrations in the bulk solution.

Jan 1, 1993

Jan 1, 1993

By Robert Rautenberg, Ted Budd

The paper will discuss the successful construction of the largest dollar value ($194.5 million, U.S.) TARP (Tunnel and Reservoir Plan) project built to date for the Metropolitan Water Reclamation District of Greater Chicago. The mining and lining of the 18.5km (11.54 miles) tunnels will be emphasized. The tunnels were driven utilizing three TBMs ranging in size from 9.85m (32.33 ft) to 3.70m (12.16 ft) in diameter. The operations surrounding the 11,546m (37,876 ft) long 9.85m (32.33 ft) diameter tunnel will be highlighted. A total system concept was utilized to attain mining rates up to 29.3m (96 ft) per shift and lining productions of 58.5m (192 ft) per day. The reliability of these systems was instrumental in the completion of the project more than a year ahead of schedule.

Jan 1, 1995

By C. Rodgers, E. (Ted) Warren

"LocationThe Key Lake operation of Cameco Corporation is located at latitude 57°N in northern Saskatchewan, within the southem boundary of the Athabasca formation. The nearest city is LaRonge, located 240 km to the south. Access to the mine is by all-weather road and by private airstrip.Description of OperationThe mill was designed to produce twelve million pounds of uranium oxide (U3O8) a year from a feed grade of 2.4% U3O8. Current production is fourteen million pounds from 2.0% feed.Following grinding, the uranium is leached using sulphuric acid and oxygen in autoclaves. An eight thickener counter current decantation (CCD) circuit is used to separate the uranium-bearing solution from the solid waste residue. The uranium in solution is further purified in a solvent extraction circuit. The purified uranium is then precipitated using ammonia, calcined at 840°C, and packaged in drums for shipping to refineries. There is a crystallization circuit to recover excess ammonium sulphate produced in the process, and a waste treatment circuit.HistoryUranerz Exploration and Mining discovered the Gaertner and Deilmann orebodies in 1975 and 1976, respectively. Between 1975 and 1977, Uranerz conducted laboratory studies and delineated a process for the Key Lake ore known as the ""Bonn process."" In 1977, Sherritt Gordon Mines Ltd. was retained to conduct further studies in cooperation with U ranerz. The technical feasibility of the Bonn process was generally confirmed. Howeve1~ alternative processing methods also appeared feasible, and over the period 1978-1979, a detailed research and development program was conducted to finalize the processes to be used and to provide data for design of the plant."

Jan 1, 2000

By B Maybee

In underground mine planning, many potentially value-eroding decisions are made due to a lack of time and proper evaluation practices. The information required for mine planning decisions goes beyond external sources of uncertainty that are recognised by typical evaluation techniques used in the mining industry, to include technical factors (eg mine development layout) and the ability of a mineral extraction project to achieve its anticipated production levels. Due to the individual characteristics that define underground mining projects, each will exhibit a different risk profile, and thus advanced optimisation and evaluation techniques are required to capture this information.As underground mine planning tools become more sophisticated, mine planners have the capacity to investigate numerous mine sequencing options to identify the best strategy for a given project, creating higher value for shareholders. This paper describes a risk-based evaluation methodology (RbEM) that accounts for financial and technical risk in the evaluation of underground mining projects. While the use of the RbEM has been described in previous works, no benchmarking of the benefits that can be realised from a change in those decisions that are made early in the process has been undertaken. To show the benefits that can be achieved from using the RbEM, this paper updates a case study to which the RbEM was applied, and takes a retrospective look at whether additional value would have been gained by following the strategic recommendation of the RbEM versus a typical optimisation exercise that aims to maximise the net present value.CITATION:Maybee, B, 2012. Can a risk-based evaluation provide a more valuable mine design?, in Proceedings Project Evaluation 2012 , pp 53-58 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 24, 2012

By H von Blottnitz, A C. Keith

The influence of the life of a mine extends beyond its immediate vicinity both in geographic and temporal terms. Decisions around mine approvals are generally made based on economics, for the mine owner and immediate environmental and social impacts by governments and communities. The value from life-of-mine planning can also be viewed in a holistic frame across the entire value chain from mine to product user. This research examines the Carmichael Coal Mine in light of the holistic benefits and impacts along its value chain from the mine to relieving the lot of energy poor in India.CITATION:Keith, A C and von Blottnitz, H, 2016. Can Australian coal alleviate energy poverty in India – a case study, in Proceedings Life-of-Mine 2016 Conference , pp 52–56 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By Paul C. Schmall

In recent years, several geotechnical methods have been successfully applied to ash pond closure. These include modified dewatering techniques with wellpoints and wells to physically drain the material, soil mixing to create a soil-concrete material for improved accessways as well as improved ground structures within ponds to act as barriers or gravity dams, and geotechnical instrumentation to serve as an early warning of the potential for liquefaction. Given the parallels between fly ash and sluiced in place mine tailings, the application of fly ash remediation method to mine tailings shows significant potential, as illustrated in this paper.

Feb 1, 2024

By L. Lipsett

"Human rights can contribute to sustainability in the mining sector, both in theory and in practice. Both human rights and sustainability share a common concern to improve economic prosperity, environmental health and social equity by avoiding negative impacts and conflict, as well as by engaging with and empowering affected communities. Globally, there is an emerging consensus that companies have a responsibility to respect international human rights standards. Respecting human rights means that mining companies are responsible to ""do no harm"" to the people and communities affected by their operations. After a discussion of the Protect, Respect and Remedy framework for business and human rights, this paper illustrates some examples of how international standards for human rights and sustainability interacted in a recent assessment of Goldcorp's Marlin Mine in the Western Highlands of Guatemala. The final section explores how human rights should be integrated into broader policies and procedures for corporate sustainability. This includes integrating human rights into ESIA processes, legal compliance, corporate governance and grievance mechanisms. Pressures on mining companies to respect human rights will not disappear; therefore, a proactive and integrated approach to human rights is a fundamental component of a broader strategy for sustainability"

Jan 1, 2011

By K. Lapakko

One responsibility of the Minnesota Department of Natural Resources is to encourage the development of mineral resources within the state. A second responsibility is to ensure that mineral development does not adversely impact other natural resources, including the water resources of the state. One approach the Division of Minerals has taken to fulfill these responsibilities is to conduct cooperative research with the mining industry. To encourage mineral development the Division has cooperated with industry on projects related to exploration, mining, and mineral processing. To examine environmental issues the Division has worked in concert with iron ore, base metal, and precious metal exploration and mining companies, as well as the Western Governors' Association, US Bureau of Mines, US Bureau of Land Management, and the US EPA for the past 20 years. These projects were conducted to evaluate methods of predicting, preventing, controlling, and treating problematic mine waste drainages, as well as mine waste revegetation. This paper I) briefly summarizes cooperative projects conducted, 2) enumerates elements which have contributed to the success of cooperative projects, and 3) describes changes implemented for future projects at the Division's new field and laboratory research facilities, as well as at existing mine and plant sites.

Jan 1, 1998

By D Thornton, B Smith, S Demey

Mine to Mill (MTM) optimisation, a total systems approach to the reduction of energy and cost in mining and mineral processing operations, is well-established technology. However, successful applications of MTM optimisation have been largely confined to gold, copper and lead/zinc semi autogenous grinding (SAG) operations, where the goals of tweaking the blast design to increase fines and hence throughput through the mill have been relatively easy to meet. The application of MTM optimisation in a more demanding environment, like that of a multi-stage crushing and screening aggregate operation, was conceived as part of a Department of Energy (DOE) initiative in 2004, aiming to reduce the energy consumption in the US aggregates industry. Two quarries operated by the Luck Stone Corporation of Richmond, Virginia, were selected for the demonstration sites. Dealing with ore variability and a requirement to maintain a fixed feed size distribution to the tertiary plant, whilst still aiming to increase yields of saleable products, presented some unique challenges. Despite these variables, the implementation of the MTM approach at Luck StoneÆs aggregate plant in Pittsboro, North Carolina, has led to a tangible improvement in productivity, particularly in the primary and secondary plants. The successful outcome was dependent upon several key factors, including reliable blasting and processing models, careful analysis of the rock conditions and plant configuration, understanding and buy-in from the Luck Stone operations staff, excellent collaboration with Virginia Tech staff and students, and long-term monitoring made possible through comprehensive PLC logging. This paper presents a review of the work conducted at the Pittsboro quarry and highlights the key reasons behind the successful implementation of the MTM approach in a complex plant environment.

Jan 1, 2007