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By Michael Li, Kathryn Rogers, Arie Moerman, Mike Cooper

The Brunswick Mine, a Division of Noranda Inc., produces zinc, lead, copper, and bulk lead-zinc concentrates through underground mining of a large massive sulphide deposit. The mining method employed is longhole open stoping with delayed backfilling. In 1996 Brunswick began a review of its mining methods and backfilling operations. In 1997 the decision was made to convert the backfill system from cemented and uncemented rockfill to paste backfill prepared from mill tailings. This paper will describe the features of the backfill preparation and distribution systems, review the handling of technical issues, and discuss experiences since plant commissioning.

Jan 1, 2001

By M. Nambiar

Due to the remote locations of the mining projects and the demand for long transmission lines to provide electrical power, mining sites often operate with poor network power quality and low short circuit capacity. In order to cope up with this situation, more and more mining projects are considering the installation of appropriately designed Synchronous Condensers(SC) together with Power Factor Correction and Harmonic Filter System(PFC&HFS). The installation of these power quality equipments is viewed as a technological advancement in the mining application. An adequate level of short circuit power is essential and has to be ensured for the safe and reliable operation of especially large cycloconverter driven gearless mill drive systems used for grinding application. Increase in plant short circuit power is generally achieved by lowering the impedance of the supplying network. The SC also provides smooth voltage control during mill starting or major load trips, thereby regulating the plant voltage within the required limits. This paper will explore the impact, technical advantage and reasoning for the selection of the advanced hybrid technology mentioned above, in order to cope with the power system challenges for future mining projects. It also highlights the potential problems and how to address them carefully.

Feb 23, 2014

By Ping Zhang, Xu Ma

Perturbations from mining operations significantly affect the stability of rock masses, especially with the increase in mining depths. This study uses the discrete element method (DEM) to investigate shear slip failure along discontinuities in an underground mine, aiming to quantify seismic moment and seismic energy to better understand seismic hazards.

May 1, 2023

By Irving Hauser

The determination of new ways to cut costs in then times of economic uncertainty is essential in running a successful business. Arco Petroleum Products Company a Division of Atlantic Richfield Company recognized an opportunity for a substantial cast savings in transporting calcined petroleum coke to market by simply building an economical port facility at a location that would enable them to drastically cut their normal rail haulage distance.

Jan 1, 1982

By Gordon J. Hughes

The ldaho Cobalt Belt represents a unique geologic environment containing some of the largest known reserves of cobalt in the United States. Stratabound cobalt-copper-gold deposits formed within a sedimentary basin that was generated by the rifting of an Archean cratonic block. Host rocks for these deposits are the Early to Middle Proterozoic Yellowjacket Formation comprising a suite of clastic sediments, volcaniclastics, and mafic tuffs that accumulated in the intracratonic rift basin about 1.7 b.y. ago. Rifting was probably initiated during a regional heating and doming event that may date back to 1.8 b.y. ago. During this time, other rift basins were likely to have formed in the region. They probably represent the precursors of a much larger depositional environment having characteristics of an Atlantic- type or passive continental margin where younger formations of the Belt Supergroup were deposited. The Yellowjacket Formation has been subdivided in the Idaho Cobalt Belt into three genetic units representing various subenvironments of a deepwater clastic fan complex. A northwest- trending deep-basin structural trough accumulated fine-grained muddy sediments that were periodically interrupted by distal turbidites of the subaqueous fans. Subsequent progradation caused the deposition of coarser-grained clastics of the more proximal portions of the fan complexes. Submarine fan lobes were built across northwest-trending tectonically active basin growth faults. These in-basin structures caused a great deal of penecontemporaneous deformation within the Yellowjacket sequence. Northeast-trending fault zones formed an orthogonal set of fractures that controlled the shape and size of sub-basins, and were also an influence on lateral migration of dominantly fine-grained clastic material. The eruption of mafic tuffs at about 1.7 b.y. ago added a new component to the Yellowjacket sedimentary sequence. Around the Blackbird mine area these tuffs commonly occur either near the base or within some of the sandier sequences. Since most of the sand influxes were largely controlled by basinal tectonism, the tuffs were probably erupted during tectonically active periods of basin development. The dynamic nature of the sedimentary environment probably caused much of the tuffaceous component to be mixed with other clastics and even resedimented as volcaniclastic material. In time, the change to a higher energy sedimentation regime resulted in such a dramatic clastic dilution of the tuffs that they could not survive in the areas of the vents, and, if present, they must have been distributed elsewhere in the basin.

Jan 1, 2013

By Louis J. Czel

Although lithium was first discovered by Arfwedson in Sweden in 1817, it did not reach any significant status in commercial application until 1908 when Thomas A. Edison received a patent covering the use of lithium hydroxide in alkaline' storage batteries. Edison's achievement can be regarded as a major breakthrough in the development of the lithium industry. In the years prior to 1908 lithium salts had found only modest applications in the pharmaceutical and pyrotechnic fields. The next important milestone in the growth of this net industry occurred in Germany in 1918 when Metallgesellschaft at its metallurgical laboratory at Frankfort-on-Main discovered that the addition of a few hundredths percent of lithium metal to aluminum and its alloys increased-the hardness. This brought into being a new commercial use of lithium in the manufacture of bearing metals. The new material, called "Bahnmetall" (railroad, metal), was widely used for, many years in the manufacture of bearings for railroad and automotive purposes. Its use continued until the early 1930's and there was a short-lived renewal of its production during World War II. Subsequent use of-the alloy was soon outmoded.

Jan 1, 1961

By Y. Kurokawa, R. Kurosawa, I. Iwata, I. Fukuoka, N. Sugita

INTRODUCTION The Ningyo-toge Mine is located in the western part of Honshu, about 800 km from Tokyo. Since the discovery of uranium ore deposit at Ningyo-toge in 1955, different kinds of mining and milling tests have been carried out. A new pilot plant of milling and UF6 conversion is also being under construction. Operations are scheduled to start by the end of this year. In 1979, the uranium enrichment pilot plant was constructed at Ningyo-toge and test operations have started. Thus, the Ningyo-toge area is assigned to undertake the Research and Development of the upstream of the nuclear fuel cycle in Japan. PNC has been strengthening its security measures more than ever. This paper will focus on the disposal of wasted material, especially on the disposal of heap leaching residue, in Japan. URANIUM ORE DEPOSITS The uranium of the Ningyo-toge Mine is characterized genetically by epigenetic sedimentary type deposits. They occur in the host rock of Neogene tertiary fluviatile conglomerates and sandstones which unconformably overlies the Mesozoic-Palaeogene granitic basement covered with lucustrine deposits and volcanic ejecta. More than 12 deposits have been found over the area of approximately 160 km2, and distribution of the deposits are strongly controlled by the so-called channel structure, probably remnants of paleo-streams on the denudation surface of the underlying grantic basement. Each ore body has different shape and dimension respectively, but about 2-3 meters thickness with the average grade of 0.05-0.2% U308 is common feature of the ore bodies. The ore is soft and loose, and it is composed of common rock forming minerals of allogenic origin and their altered products. The chemical composition of the ore depends on the constituents of the country rocks or the pebbles. A primary mineral, ningyoite and secondary mineral, autunite are major ore minerals, although three primary tetravalent minerals and thirteen secondary hexavalent minerals have also been detected. MINING EXPERIMENT Since 1959, various types of underground mining tests have been carried out at Ningyo-toge Mine. The room and pillar method was safe and simple, although the uranium ore recovery was below 70%. After experiment of the retreating long-wall method and slicing mining method, it was found that the modified long wall method was the most appropriate for the underground mining of the Ningyo-toge uranium deposits. This method was completed successfully to increase efficiency up to 2 or 3 times, as compared to conventional methods. MILLING EXPERIMENT In 1964, a small test mill was constructed at Ningyo-toge, and a milling experiment using the Ningyo-toge uranium ore was started. Re-modelling of equipments and improvement of the process lead to the establishment of the technique of the so-called wet process, and produce UF4 directly from the ore. The flow diagram is shown in Fig. 1.

Jan 1, 1981

By Dominick Mandalari, David Mast, Heather Ullinger, Juan Granja, Amanda Foote

The City of Akron will construct the Northside Interceptor Tunnel (NSIT) project to control and reduce combined sewer overflows. One component of the project a large diameter tunnel diversion / flow control structure that will facilitate tunnel storage, divert dry weather flow to the treatment plant, and divert large wet weather events that are greater than the tunnel capacity to the Cuyahoga River. The structure is designed to pass up to 1.2 billion gallons per day of flow and includes floatables screening. This paper will discuss project background, factors that influenced shaft location, and options evaluated to manage the large design flows.

Jun 23, 2024

By J. Gawler

In June 2005 the Minerals Council of Australia signed a Memorandum of Understanding (MoU) with the Australian Government which states an intention ?for mining companies and government to work together with Indigenous people to build sustainable, prosperous communities in which individuals can create and take up social, employment and business opportunities in mining regions?. Implementation of the MoU has begun with demonstration sites established across Australia. All sites are using a Regional Partnership Agreement (RPA) model as a framework for enabling local people to find local solutions to local issues in partnership with mining companies, governments and Indigenous communities. Mining and resources companies can provide important input into regional economic development and capacity building by working through local partnerships. Company benefits include gaining a social licence to operate, access to a reliable skilled workforce, better longterm relationships with Indigenous communities and sustainable regional communities. All levels of government, Australian, State and Local, are working collaboratively to address unemployment and other issues in remote Indigenous communities. The Australian Government has adopted RPAs as one mechanism for implementing its whole-of-government approach to Indigenous affairs. This leading edge work is unique to Australia and the model has applications and significant learning for other countries and industries.

Jan 1, 2007

By N. Djordjevic

The vibration energy that travels beyond the zone of rock breakage is wasted - all it does is cause damage and annoyance. Under favorable geologic conditions, this energy may travel many kilometers before it finally drops bellow the background noise level. This has forced the introduction of more restrictive limits to the allowable vibration levels. To maintain the profitability of a mine or quarry and to comply with environmental protection legislation, blasting needs to be performed in a more predictable way that will ensure that the final results are optimal in both mining and environmental terms. Minimization of ground and induced structural vibration is, therefore, a matter of good blasting practice - not just an attempt to avoid complaints from neighbors. A new approach to blast vibration minimization is presented. The method utilizes the existence of the local minimums in the frequency spectrum of single-hole blast vibration. The results are presented as a delay map showing maximum ground or structural vibration velocity for many combinations of interhole and interrow delays. A blast engineer can use this map to select an optimal combination of delays that will produce a low vibration velocity at a selected location and, at the same time, will be acceptable from the point of view fragmentation or muck pile shape.

Jan 1, 1997

By W. C. Lacy

It is the responsibility of educators to look ahead and prepare young engineers and scientists to cope with industrial and social problems of the future. We are faced with a review of history as well as prophesy of the future. The mining industry exists in a "bubble" with little interaction or communication with the outside. This isolation must be broken down if the industry is to survive in the U.S. and Canada. The ability to communicate with the general public and public officials is essential. Many changes are occurring that will require readjustments in technology and staffing. Aging population will result in raising retirement and increasing available workforce. This may force shorter working weeks to supply additional jobs. Environmental concerns will likely direct more attention not only to these concerns during mining, but to planning for post-mining land usage. Retraining and up-dating educational programs are required to cope with these changes.

Jan 1, 1994

By Huijun Shao, Qiang Liu, Zhengming Yi

The increase of the proportion of high Al2O3 content iron ore fine in iron and steel enterprises has brought about a series of problems such as the increase of the viscosity of blast furnace slag and the difficulty of the separation of slag and iron. In order to solve this problem, the effect of increasing MgO content on the technical and economic index, the cold strength, and metallurgical properties of high basicity and high-alumina sinter was studied through sinter pot test. Nova400NanoSEM field emission scanning electron microscope was used to analyze sinter microstructure. The experimental results show that when the MgO content fraction in the sinter with high basicity and high aluminum increases from 1.72 to 2.49%, the vertical sintering speed decreases by 4.38mm/min, the utilization coefficient decreases by 0.51t/(m2 h), and the low-temperature reduction degradation index increases by 6.7%. When MgO content in sinter is 2.11%, drum index and reducibility index are the highest, reaching 61.93% and 86.39% respectively. Mg2+ is mainly solid dissolved in the magnetite lattice and replaces Fe2+, up to 3.64%. The generated magnesie-containing magnetite inhibits the phase transition from Fe3O4 to Fe2O3 oxidation process in the sinter cooling process, which reduces the generation of secondary hematite and is conducive to improving the low-temperature reduction degradation performance of sinter.

Jul 4, 2021

By E. Wm. Heinrich

Glass sands fall into that extremely select category of mineral deposits that requires a fantastic degree of natural concentration (95% +) of a single component before they can even be considered as ores suitable for further refinement. The combination of geological factors that has produced such an environment of "mineralogical single-mindedness" has appeared only rarely. Factors that require consideration in the economic evaluation of a potential glass-sand deposit can be grouped into three categories: 1) geological (e.g., size, shape, structure); 2) petrographic (e.g., grain size, accessory minerals, nature of iron contaminants); 3) geographic - political (e.g., proximity to consumer, size of market, zoning restrictions). Of particular con ern is the nature of the iron contamination. Iron-bearing species appear as 1) accessory mineral grains, either detrital or authigenic, 2) cements, 3) grain coatings, and 4) quartz-grain inclusions. Selection of the cheapest form of beneficiation requires precise information on the mineralogy of the iron species and their detailed petrography. Because of the antipathetic relationships, in many parts of the United States and Canada between the geographical locations of glass plants and the geological distribution of glass sands, the selection of ac suitable source for a particular glass plant may be dichotomous. One may seek either an exceedingly pure "classic" type glass sand that is relatively distant and whose cost includes a major transportation charge or a relatively proximate and somewhat "impure" source whose cost includes a substantial fee for beneficiation.

Jan 1, 1974

By Rodney R. Krause

In attempting to tell the general public about the coal industry's land reclamation efforts, we have often said, "We're not doing things by the book, because we're still writing it." Like any good catchphrase, the statement is not only striking but true. It is particularly true in the mountains of Appalachia, where the problems of mining; and of reclamation are made more intense by the nature of the terrain. Mining and reclaiming the land "by the book' --which is to say by the methods of contour mining traditionally used in hill country--hasn't worked too well. So a lot of conscientious coal operators and associations are trying new methods--new ways of mining, new machines for seeding and planting, and new species to seed. Not all their experience can be transplanted to other areas, and of course I don't believe that Appalachia is the only place where new methods are being developed. Nevertheless, there's enough action in Appalachia to make a detailed examination rewarding, so let's focus on the hills to see what's new.

Jan 1, 1970

By D. W. Mitchell

Planning today for what hopefully will never happen is one of the surest ways to decrease the chance of it happening. As Napoleon proved and Ian Mitroff wrote, "The heat and stress of battle is the worst time to make decisions of strategic importance." Mitroff also wrote, "The value of a plan is not that it will ever perfectly match reality, but going through the process of planning speeds the process of recovery. It allows the organization to emotionally work through the worst before it actually happens." This paper concentrates on things miners must consider; on the need for plans to be like a belt conveyor strong enough to carry the load, flexible enough to stretch a little; on the criticality of throwing away fax machines and telephones, and having certain officials at the scene rather than back in head-quarters; on the training of fire brigades and mine-rescue teams; on having company-controlled chromatographs; on having people who can look at trends rather than numbers. Some of the things in this paper might anger some readers; for that, I can only ask them to consider first the problem not their position.

Jan 1, 1993

By William J. Dimond

Computor analysis has opened a new world of information for the mining of resources. This paper is directed at the mining of coal. The same procedures apply to most mining projects. The available facts when evaluated against the variables produce the answers. The project must be carefully analyzed, so that the facts can be organized in a data file. The file can be expanded as additional information is obtained during the entire life of the mine. If the mine is pre-planned, the file will be expanded in an orderly fashion and updated information will be available at all times. The development of a property goes through several phases; Exploration, Economic Analysis, Development, Production, and Reclamation. Each phase is an expansion of the data file. The validity of the answers is directly related to the accuracy and quantity of available data. The basis for a data file is horizontal position, and elevation of each piece of information. A coordinate system and datum are reference for a digital (X, Y and Z) position in a spatial system, a three dimensional digital model of the mine. The current practice is to use the State Plane Coordinate system and elevations as established by the U. S. Coast and Geodetic Survey. Each state has adopted this system by law. In the event there is litigation, it is an advantage to have the data on the legally recognized system. The control must be expanded so that all data can be assigned a digital position, and planned to fulfill the requirements for all phases of the mining operation. The project must be analyzed to insure that the objectives can be achieved without duplication or loss of time. sufficient data must be available to reach each required level of information. The coal data can be defined in two categories, spatial

Jan 1, 1977

By A. K. Fallaw, G. Wang, L. R. Moore, S. Dobson, Y. Xiong, J. Gu

"As ores degrade, mining techniques and chemistries change to meet market demand and maintain product quality. The balance of recovery and grade is a significant challenge in the Crago Process where an anionic collector is used to float phosphate, followed by acid scrubbing, then an amine float to improve product grade. As the grade is a requirement for DAP and MAP production, recovery is the criteria to suffer. Phosphate losses in the amine float can bring overall recovery down by as much as 18%, creating a growing need to think outside the box to improve recovery. This paper will focus on the theory of amine tail recycling and the best methods to optimize the overall phosphate recovery by recycling the tails from the cleaner flotation step. INTRODUCTION In 2014 the total US phosphate production was down 13% over the prior year, from 31.9 to 27.1 Mt, which accounts for 12.32% of the world’s phosphate rock production. Florida and North Carolina phosphate production accounted for 80% of total US phosphate production, which was down from 85% the previous year. This decline is due in part to the closing of the last phosphate mine in Polk County, FL - which had an operating phosphate mine for over 100 years (Gurr, 2015). Another factor contributing to the reduction in contribution from FL & NC is the increasing challenges in beneficiating the remaining ore deposits. The Central Florida mining district has historically been in the Bone Valley deposit, where raw apatite was abundant with P2O5 values as high as 15%. The Bone Valley ore also had characteristics favorable to beneficiation to 27.5-29.7 %P2O5 while achieving recoveries above 86%. The move southward into the Hawthorne Formation has seen the ore feed grade hit some historic lows, and the matrix characteristics pose more challenges to phosphate producers. The Hawthorne Formation experienced lateritic weathering after the Bone Valley formation which altered the apatite to aluminum phosphate minerals, and alteration of montmorillonite to kaolinite, releasing MgO that caused the dolomitization of the top of the Hawthorne limestone (Cathcart, 1966). Elevated levels of dolomite can yield an increase in slurry viscosities, reduce production rates, and increase energy costs in the wet-acid fertilizer process. The MgO will also act to dilute grade, making it more difficult to achieve a standard 18-46-0 product (McHardy, 1981)."

Jan 1, 2016

By V. J. Hucka

Coal, which was discovered in Utah in 1849, covers about 18% of the total area. Production in 1981 vas more than 14 million tons. However, some Utah coal mines are quite gassy. If longwall face technology is applied, then a release of a high volume of methane may be expected during the mining process. Investigations on methane content have been made by use of an isothermic bubble desorbometer. The desorbable methane content of 5 m3 to 16 m3 of methane per ton of coal mined has been determined.

Jan 1, 1983

By Eugene C. Spilker

Cross country belt conveyors are becoming the preferred method of bulk material handling in the industrial complex. Installed cost, maintenance, reliability, simplicity and operating expense enhance this choice, especially when faced with rising cost and questionable availability of liquid fuels. Conveyor flights are getting longer, faster, and higher in capacity, and are being installed in rugged terrain. Rights of way are often difficult to obtain. All these considerations lead up to design aspects well beyond those for in-plant conveyors. This paper points out some of the aspects that lead to the successful design of a cross country belt conveyor system.

Jan 1, 1980

By Steven W. Hunt, Gregory C. Baker, Glen J. Rorison

Microtunneling methods were utilized beneath pile-supported clarifier basins to replace settlement damaged sludge drain lines at the Jones Island Wastewater Treatment Plant in Milwaukee, Wisconsin. To minimize the risk of blockage and expensive recovery of a microtunnel boring machine against pipe piles or construction debris, a Soltau RVS 80 was utilized. This machine allowed the alignment to be initially bored with guided 114-mm diameter rods to ensure proper alignment and lack of obstructions. Casing pipe was then installed by jacking 1-m long, 305-mm diameterclay pipe along the rods and behind an auger head. This case history also discusses how 2.4-m diameter precast concrete pipe was used as a one-pass sinking caisson for workshafts and new cleanout manholes.

Jan 1, 2001