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By John W. Cole

The Butte district has been the principal producer of metallurgical-grade manganese in the United States since World War I. Manganese dioxide nodules are produced from rhodochrosite ore by concentrating the rhodochrosite and roasting the concentrate in rotary "cement-type" kilns. The Anaconda Copper Mining Co. is the only producer at present. Under the stimulus of a purchasing program administered by Metals Reserve Company during World War II, however, several independently owned or operated mines (including the Norwich) produced manganese carbonate ore. These mines were examined in Juno 1949 by John W. Taber, mining engineer, Bureau of Mines. A core-drilling program to develop ore in the Norwich mine was recommended and approved. drilling was completed early in 1950. This report gives factual data obtained.

Jan 1, 1951

By Paul R. Wieber, Atam P. Sikri

This paper describes the U. S. Energy Research and Development Administration's (ERDA) program to develop in situ coal conversion processes, especially gasification. The potential of this technology, the technical directions being explored, and the program strategy to carry the process concepts toward commercialization are emphasized. The geographic location of the U. S. coal resources and a market analysis are described. Commercially successful in situ coal processes could add over a trillion tons of coal to the U. S. coal reserves. The economics of these processes is compared with surface gasification. Independent studies show this process to be 25% cheaper than surface gasification for Western coals. The major projects are briefly described. The Linked Vertical Well process is in the most advanced stage and shows great promise. The last test produced a low-Btu gas averaging 171 Btu per standard cubic foot for average production rates of 8.5 million standard cubic feet per day. The other projects are Packed Bed, Longwall Generator, and Steeply Dipping Beds. Unique factors of the process development are discussed which may lead to commercial processes in the near term. A development strategy is proposed by which this technology could be commercialized before 1983 with potentially lower gas prices and lower environmental impacts, relative to mining plus surface gasification.

Jan 1, 1979

By E. O. Bennett

Various methods of making leakage tests have been tried during a study of losses in the transmission of natural gas. This work has been carried on by the Bureau of Mines in cooperation with the Natural Gas Association of America. Results of tests show that the "shut-in pressure-drop" method described by Rawlins2 is the most accurate and reliable; therefore its use is recommended. This paper describes a graphic method for computing the rate of leakage from the fall in pressure and change in temperature determined by the "shut-in pressure-drop" method of testing. METHOD OF MEASURING PRESSURE DROP The gas is "shut in" the line to be tested and is not allowed to escape except through existing leaks. The leakage causes the pressure in the line to fall. The change in pressure is obtained with a dead weight gage. Approximate results may also be obtained from readings on a good spring test gage. Numerous tests show that the dead weight gage is more sensitive to small changes in pressure than spring gages.

Jan 1, 1926

By H. R. Bullis

Lupin is located on the shores of Contwoyto Lake at lat. 65° 48'N, Long. 111° 15'W and lies about 80 kilometers south of the Arctic Circle. Since start up in 1982 the mine has produced over 2.15 million ounces of gold from 6.66 million tonnes of ore grading 10.63 gm/tonne. Total remaining reserves at 1993 year end were 5.1 million tonnes at a grade of 9.11 gm/tonne (1.65 million ounces). This is sufficient for 7 -8 years at the present annual production rate of about 200,000 ounces. The Centre and West Zones of the deposit are open to depth. The deposit is in an Archean metaturbidite sequence of the Contwoyto Formation, which has been mapped as part of the Yellowknife Supergroup of supracrustal metasedimentary and metavolcanic rocks making up part of the Slave Geologic Province. These rocks have been subjected to regionar and contact metamorphism and to several phases of deformation. Six stages of Archean plutonism have been identified and all Archean rocks have been cut by Proterozoic diabase dyke swarms. Gold mineralization in the Lupin deposit is commonly fine grained and associated with pyrrhotite and arsenopyrite in amphibolitic banded iron formation. The gold-bearing portions of the host iron formations are characterized by the presence of multiple quartz veins and the pervasive replacement of grunerite by hornblende. In sparsely mineralized portions of the host iron formation, zoning of sulfides about quartz veins is clearly seen with the arsenopyrite halo being more restricted around the veins than the pyrrhotite halo. In well mineralized portions, quartz vein densities approach one vein per metre along strike. In these areas pyrrhotite distribution in the iron formation is more pervasive and the rock takes on the appearance of a banded sulphide rock.

Jan 1, 1995

By John M. Dale

Now that the price of sulfur has reached unexpected high levels, it is little wonder that sulfur from surface ores is again receiving attention. In most instances, it is advantageous for an ore to be at or near the surface. However, it is a distinct disadvantage for sulfur ore to be close to the surface because it precludes the use of the Frasch process. The Frasch process depends on the presence of at least 180 m of uniform overburden to allow pressure injection of superheated water into the sulfur-bearing formation to melt the sulfur. In the Frasch process, sulfur separates cleanly from the gangue underground and comes to the surface in a very pure form. Surface sulfur deposits, particularly those in the Western Hemisphere, exist largely due to volcanic activity, and sulfur separation from the gangue is a formidable technical problem. None of the surface deposits are large compared to some of the Frasch deposits, but at the present sulfur price, they are certainly of economic importance. From the turn of the century until 1975, the price of sulfur was for the most part $18-$28/t. However, with the price of sulfur now over $154/t, there are a variety of technical alternatives to consider for sulfur surface ore separation that may not have been economically attractive a few years ago.

Jan 9, 1981

By J. -F. Lagueux

Goldex Mine is an underground mine located near the town of Val-d?Or. Multiple innovations were required to work the mine. Due to its low grade, it was important to develop a bulk mining method to economically extract the ore. The method used is a combination between shrinkage stope and long hole stope methods. This modified method is more than adequate; however, all of the ore body must be liberated in a very short period of time. Therefore, to bring down 23 Mt of ore, large blasts up to 1.8 Mt are required. The situation is also complicated by the fact that the mine is located in a residential area. No less that 40 homes are built within a 1 km radius of the mine site. In addition to managing mass blasts, means must also be found to mitigate the vibrations produced by the blast to diminish the disturbance to the neighbourhood. Therefore, the mine used numerous tools to properly plan the blasts and reduce the impacts. A program to control vibrations was one of the first tools put in place. The program?s aim was to draw up an action plan to ensure a follow-up of the homes by inspecting them. The second tool was to develop a methodology to plot a reliable attenuation curve and to adequately determine the maximum charge weight for each blast. Finally, effective communication tools were developed to inform the neighbourhood. There was a huge amount of work to be done in relation to the bench. Reliable and fast loading techniques had to be found to load large blasts in a very short period of time. Adequate logistics had to be developed to send underground more than 20,000 kg of emulsion per day while performing the daily underground operations. Technology had to be developed to adapt the i-kon electronic blasting system to large blasts. Since the control of the charges was the major factor to reduce surface vibrations, it was important to employ loading techniques that would permit decking of the long holes to reduce the charge weight per delays without adversely affecting the loading. All of this work requires an enormous amount of energy but also close collaboration between the different stakeholders (various departments, suppliers and consultants).

Jan 1, 2011

By B. A. Bancroft

A quality assurance program consists of all those activities aimed at providing confidence to the purchaser that the suppliers quality system will provide a product that will satisfy the purchaser's stated quality requirement. An organizing principle is necessary for prioritizing the quality control activities of quality personnel in the face of a myriad of technical possibilities, data-analytic applications, and an overwhelming number of possible activities promoted in the literature and by quality "gurus". The organizing principle I like is that quality assurance exists when those involved in the quality process: (1) know what they are supposed to do, (2) can tell if they are doing it and are set up to continue doing it and, (3) if they are not, they can remedy the situation in a timely fashion. Any incremental activity which facilitates this organizing principle is a continuous improvement activity. That activity which has the chance to facilitate this principle to the greatest extent is the next one to work on. In these days of lean corporate and regional staffs it is as important to know what not to work on as it is to know what to work on. In this paper I shall discuss in general terms the implications of this organizing principle for the design of Quality Assurance (QA) Programs for coal mines and also provide some comments about the application of Statistical Process Control (SPC) methodologies in the coal industry.

Jan 1, 1994

By P. Lopez, E. Wellman, N. Risso, A. Anani

Current machine learning models used for roof fall hazard prediction are mounted on expensive sensors, computationally expensive, or lack the robustness for accurate prediction in the underground mining environment. This research aims to provide a design methodology for a robust, low-cost, deep learning-based algorithm for underground mine roof fall hazard prediction. A data sampling plan is developed to ensure the replicability and robustness of the developed model. In addition, feature engineering and transformation methods are described to identify relevant features for hazard identification. The methodology described here will be used in model development, tested, and implemented as a real-time mobile device application. The new tool will be expected to detect roof fall hazards in real-time and contribute to a crowdsourcing approach for underground hazard detection.

Feb 1, 2023

By John B. Goddard

In-situ leaching of uranium by aqueous ammonium carbonate containing oxygen or hydrogen peroxide as oxidant results in the partial dissolution of sulfides. While some of the sulfide sulfur is oxidized to sulfate, a considerable portion is oxidized only to thiosulfate and polythionates. Polythionates poison the anion exchange resin used to extract uranium. At the Palangana operation in southeast Texas, the trithionate ion (S3062-) was found by infrared spectrometry to be the major resin poison. Treatment of ion exchange feed solutions with hydrogen peroxide only resulted in partial conversion of reduced sulfur species to sulfate, and trithionate conversion was particularly slow. Poisoning of the resin also occurred from the ammonium chloride eluant, which built up trithionate because of recycling. This was essentially eliminated by chlorinating the eluant prior to yellow cake precipitation.

Jan 1, 1984

By Viviane Tavares

The liquid crystal display (LCD) are currently known by its vast application in electro ? electronic devices, amongst them can be detached the devices of TV, laptops, electronic date, calculators and even though the mobile telephones (mobiles). The mobiles are changed more frequent of the TV for example, this happens due to the technology advance. With the constantly mobile exchange, the batteries, printed circuit board and liquid crystal display accumulation its become an environmental problem. To minimize the environmental impacts caused by mobile telephones residues are considered the segregation process of the LCDs main components, to goal to recover the recycle material. This process involves the use of treatment ore techniques with disc, hammers and balls mills. The process with best efficiency (about 98%) of LCD glass release was the hammers mill. The glass recovered can be used in the glass recycling and the sand substitution in the production of concrete blocks.

Jan 1, 2009

By William R. Bush

This paper is a presentation of findings based upon an econometric model of the world zinc industry. The model was developed as a simple but useful aid for long-run forecasting and planning purposes. A structure was developed for both simulating real zinc price effects on production and consumption, and for forecasting long-run annual zinc prices and supply/ demand levels. Moreover, a methodology is provided to incorporate the effects of: (1) historic technological advances in zinc supply, and (2) the development of the competitive plastics industry. Finally, reduced form equations are used to generate ex post forecasts to evaluate the model's performance.

Jan 1, 1979

By A. J. Kraemer

This report on the physical and chemical properties of crude oils of California is one of a series on the producing districts of the United States. It includes a short discussion of results, tabulated data, and individual analyses of California crudes. Analyses of crude oils from the fields of Fresno, Kern, Los Angeles, Orange, and Ventura Counties have been published in Serials 25952 and 26083. The analyses reported in this paper corer samples that were obtained subsequent to the publication of Serials 2535 and 2608. The samples were obtained by members of the San Francisco office of the Bureau of Mines. The collecting of samples was facilitated by the courtesy of representatives of oil companies in California.

Jan 1, 1927

By A. B. Cecala

It has long been known that ventilation is a cost-effective method to lower respirable dust concentrations in all types of mining applications. The National Institute for Occupational Safety and Health has been working on a number of different research techniques that use ventilation as a critical component to lower respirable dust levels at surface and metal/nonmetal operations in the United States. This article presents five such research efforts. The first research area discusses how improving the ventilation flow patterns in an iron ore mill facility lowered respirable dust concentrations by 31 pct throughout the primary grinding area. The second research area examines how respirable dust levels were lowered at a dimensional stone shop by using air cleaning units suspended from the ceiling. A third area discusses how improvements in ventilation at underground limestone mines lowered respirable dust concentrations. The fourth area examines how improvements in dust filtration and pressurization systems significantly impacted the air quality in enclosed cabs of surface mining equipment. The last area presents a newly developed clothes cleaning technique. This technique uses an air spray manifold to blow dust from a worker?s clothing in an enclosed booth, which confines the dust for capture and removal by a baghouse dust collector. These research areas represent an array of different control technologies to lower respirable dust concentrations. Ventilation is an integral part of these control technologies.

Jan 1, 2006

By P. Somasundaran, D. R. Nagaraj, Tarun Bhambani, P. Patra

Flotation separation and recovery of value minerals from ores containing fibrous silicate minerals are known to be quite challenging. Earlier studies have established that the metallurgical challenges (poor selectivity and recovery, high energy consumption, etc.) arise from the impact of the fibrous minerals (with high aspect ratio) on pulp rheology, which was found be rather complex. The complex rheological behavior of ore suspensions containing particles with high aspect ratio and its influence on flotation outcome are investigated in this study. Flotation tests and rheological measurements were carried out with both ores (containing fibrous minerals) and a model system comprising nylon fibers (chemically inert) added to a copper ore that had no fibrous mineral. These studies allowed the determination of contributions of physical properties of the fiber to pulp rheological behavior. Optical microscopy images of the fiber pulp indicated that the fibers entangled to form two levels of microstructures: two-dimensional (2D) aggregates under semi-dilute (< 20% solids) conditions and three-dimensional (3D) microstructures at concentrations > 30% solids. The yield stress (σ) values determined for the fiber pulp were logarithmically related to the volume fraction of the 2D/3D structures. The relationships developed here for different ARs showed that the yield stress of a flotation pulp changes with respect to shape, size, and the concentrations of the microstructures. Implications to the effects of such entangle networks on selectivity of flotation separation are discussed.

By S. Parent, J. -F. Lepage, S. Glover

"Goldcorp – Eleonore’s 7 000 tonnes per day gold mill was started up in October 2014 and achieved commercial production in April 2015. During the first year, operation has faced challenges from grinding, flotation, sulfide cyanidation and tailing filtration to achieve targeted throughput, availability and recovery.The optimization of non-sulfide tails filter cloth lifetime and filter press availability had the most significant impact on ramp-up of both mill throughput and availability. A change in steel ball addition size to the grinding circuit was made to meet the targeted p80 of 65 µm. Various optimization efforts were conducted on the flotation circuit, intended to recover all sulfide-bearing minerals. The goal is to attain the environmental target of 0.12% sulfur in flotation tails (to eliminate acid mine drainage or AMD), while an average of 0.31% sulfur was obtained over the first months of 2015. Collectors, frothers, activators and hydrodynamic parameters were tested to improve the circuit desulfurization efficiency. High sulfide reactivity in pre-oxidation and cyanidation severely impacted dissolved oxygen levels and cyanide consumption. Studies were undertaken to understand the effects of mineralogy, grind size and leach conditions on gold dissolution kinetics and cyanide consumption. Efforts were focused on pre-oxidation to restore dissolved oxygen levels as well as optimizing both lead nitrate addition and pre-oxidation time.INTRODUCTIONGoldcorp Eleonore’s mill commissioning started in September 2014. It was considered to operate the mill at 3 500 tpd during design, as the mine was planning to operate at this throughput for the first year. However, with the stockpile of ore and a higher throughput from the mine, the mill was able to run at higher tonnage than initially anticipated.While increasing tonnage, a few bottlenecks were discovered and overcome in areas such as filtration and cyanide destruction. There were also recovery issues which were addressed in areas such as grind and sulfide leach. This paper focusses on the first complete year of operation ending September 30th 2015. A process description and the flowsheet are presented below and it will then go into detail about operational, metallurgical, mechanical and design issues experienced during the year."

Jan 1, 2016

By A. Alonso, J. Daubenspeck

In the nickel extraction process at Nicaro, Cuba, dried and ground nickel bearing laterites are reduced at 1300-1400F in multiple-hearth furnaces. Nickel is leached from the reduced ore by aeration in an aqueous solution of ammonium carbonate. Nickel carbonate is precipitated from the liquor and calcined to yield nickel oxide. The following are the more important modifications of the Nicaro process since plant rehabilitation and expansion. Ten percent increase in tonnage was achieved without decreasing the fineness of the ore by minor mechanical modifications of the grinding plant. Another five percent increase in tonnage was attained by intentionally overloading the ore prepration and leaching circuits in an effort to control cobalt extraction. Modifications at the sintering plant allowed it to handle the entire output of the expanded plant. A fifty percent increase in leach liquor cooling facilities alone provided an increase in nickel production of five percent. Stronger fresh leach liquor for increased nickel washing efficiency was obtained through improved distribution of water to the ammonia absorption towers. Advantage was taken of the reduced calcine&apos;s capability to precipitate cobalt, and modifications in the leach liquor circulation provided controlled cobalt solubility with minimum harm to nickel extraction. Several process changes at the drying plant brought about a ten percent reduction in the fuel oil consumption at this pint. Controlled air addition to the reduction furnaces&apos; upper hearths burned formerly wasted combustibles thereby reducing oil consumption by twenty percent. The nickel extraction process successfully emplayed on the extensive but lowgrade lateritic ores of Eastern Cuba at the U. S. Government owned Nicaro plant, has been previously described in various publications. The large mine and plant operated by the Nickel Processing Corporation, located on the northeastern shore of Oriente Province, have been recently expanded to a yearly capacity of about 50 million pounds of nickel. Essentially, the operation involves open pit mining of a limonite-serpentine ore mixture containing 1.3 to 1.4 percent nickel and 34 to 38 percent iron. The comparatively lumpy, wet (25 to 30 percent moisture) ore is first dried and ground prior to chemical treatment, to which the entire 7,000 tons per day feed must be subjected. In the initial chemical action the dried and ground ore is reduced with carbon manoxide and hydrogen at 1300-1400° in multiple-hearth furnaces. The resulting metallic nickel is selectively leached from the reduced calcine by aeration in an

Jan 1, 1961

By William H. Schiffbauer, Timothy Lutz, Michael R. Yenchek

The National Institute for Occupational Safety and Health (NIOSH) Pittsburgh Research Laboratory (PRL) participated in an experiment to facilitate the remote control of dozers used on coal stockpiles. The experiment consisted of supplementing the normal sensory cues an operator requires to manipulate the dozer from a remote location. NIOSH provided and tested a vision systems intended to give the operator the ability to operate the dozer safely and efficiently from a remote position. This paper highlights the genesis of the experiment, identifies the contributions of Consol Energy and Caterpillar, and details the NIOSH efforts and successful test results. Keywords-remote-control; vision system; stockpiles; safety

Various influences determine how an Environmental Management System (EMS) for a mining or petroleum project is developed and administered. These influences include the environmental and resource legislation applying to the project, the culture of the organisation, the environmental sensitivity of the area, and the administrative policies of the regulatory agencies involved. While financial penalties and even imprisonment may be imposed for non-compliance with environmental legislation, there are other compelling reasons for the establishment of an effective EMS. If a company wishes to be considered by Governments for the grant of exploration or mining rights, it is important that it can demonstrate environmentally responsible operations at existing facilities. The development of an effective EMS requires commitment from the Board of the company and the issue of an Environmental Policy to empower all levels of the staff and workforce to achieve environmentally responsible operations. This must be supported by the provision of appropriate human and financial resources, and environmental training of staff at all levels from the Board to the mine site, workshop and office. A regular environmental auditing programme is essential to ensure that the EMS is in place and is effective in achieving compliance with regulatory requirements, corporate policies and protection of the environment. An EMS can be developed on the basis of existing management systems, quality management systems, existing and emerging environmental management standards (such as BS7750 and ISOI4000), or sophisticated computerised systems which may incorporate international experience, standards, and codes of practice.

Jan 1, 1995

By S Robinson, R Perkins, D Barrett, D Kepert, C Fowers

The discovery and delineation of significant mineralisation in the Eliwana region continues Fortescue Metals Group’s strong exploration success. In the decade after the first hole was drilled into Christmas Creek in mid-2004 a total of over 11 Bt of hematite-goethite mineralisation have been delineated supporting the raising of $13 B, construction of five mines, 620 km of rail and a five-berth port. As of June 2014, Fortescue was shipping at the rate of 155 Mt/a. The area including the Eliwana and Flying Fish deposits is one of a number of future growth opportunities that Fortescue is currently evaluating.The Eliwana and Flying Fish deposits occur on the south dipping limb of the Brockman Syncline/Jeerinah Anticline. The Eliwana group of deposits are hosted by the Brockman Iron Formation with the Flying Fish/Broadway group hosted by the Marra Mamba Iron Formation.Structurally the area is dominated by moderate southerly dips of the regional dome and keel style folding. The regional limb is locally cross-cut at a small angle by asymmetric north facing Ophthalmian folds trending 110&#176;. These fold sets, in part, preferentially host subsequent supergene mineralisation. Faulting is only locally apparent.Early phases of exploration commenced in 2006, with mapping of Flying Fish and reconnaissance drilling in 2007. However, due to the concurrent discovery (Clarke et al, 2009) and subsequent fast tracked development of Solomon channel iron deposit and Firetail bedded iron deposit (Simpson et al, 2011) priority was placed on developing Solomon due to its relative proximity to existing Fortescue infrastructure. Staged follow-up drilling of both Marra Mamba and Brockman targets at Eliwana was progressively undertaken from 2008 onward.As of 20 May 2014 a total of 1494 reverse circulation (RC) holes for 54 248 m and 13 diamond holes had been completed, resulting in the delineation of a Mineral Resource of 740 Mt. Exploration via mapping, drilling and metallurgical evaluation of adjacent prospects continues with additional resources expected in the future.CITATION:Barrett, D, Perkins, R, Kepert, D, Robinson, S and Fowers, C, 2015. Geological setting of Eliwana and Flying Fish deposits along the north limb of the Brockman Syncline, Hamersley Province, Western Australia, in Proceedings Iron Ore 2015, pp 219–228 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By Z. C. Shen

As core part of flotation column, aerator has been always priority research. A new type of porous aerator made of stainless sintered microcellular material is designed , which diameter is between 20µm to 40µm. High bubble surface area flux is obtained at low air pressure 20kPa by this type of aerator in water. In order to extend its applied range ,experiments were carried out in alkali slurry (pH=12) , resulting with porous aerator clogged after working 20 days . Sampling the cross-section of aerator detected by microscope and X-ray diffraction ,the reason clogging was found. Then plugging aerator was reactivated after putting it in acidic liquor treated by ultrasonic for about ten minutes. On-line aerator maintenance can be done in no down time , and it can be repetitive-used after recovered ,so reduced capital costs.

Jan 1, 2014