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By John Vynne, John Hutchings

There have been a number of recent technological advances in instrumentation for blasthole drills, and more specifically in drill monitoring and HPGPS guidance systems. Likewise, great strides have been made in the development of drill and blast software systems which are user friendly, while providing far greater capability to accurately design and monitor drill and blast patterns.

Jan 1, 2011

By María Virginia Ramírez, Alejandro Alarcón, Alea Reyes

Reactive grounds (presence of FeS2, CuFeS2) can create hazards in a mine; misfires to premature deflagration or detonation of loaded blast holes. This occurs because some minerals can react to ANFObased explosives. Due to a high potential event that occurred in The Mine in 2013, The Mine and the Explosive Provider (“The Company”) are conducting a soil characterization of the areas containing reactive sulfides. This study was planned along with The Mine and it is being developed by a multidisciplinary team.

Jan 1, 2018

By T. R. Ley

"INTRODUCTION Brutally honest mining executives will tell you that “safety is job #1 but.. dollars are also extremely important”. When economic times are tough, as they are now in mining, it can feel like you need to choose between safety and cost control. Leading edge companies know that it is excellence at both that provides the best performance. FLUID POWER SYSTEMS Fluid power systems are ubiquitous in mining – longwall systems, continuous miners, drills, haul trucks and excavators, etc. And fluid power systems are getting more powerful and using higher pressures to move greater volumes and achieve higher productivity. Average operating pressures in mobile equipment has been rising to 450 bar (6,500 psi) over the last decade. With increased system pressure comes ever increasing levels of stored energy. Stored energy that, if released in an uncontrolled fashion, can do tremendous harm to people and things.Fluid power systems are composed of pipe, flexible hoses, pumps, valves and actuators. They are filled with fluid (mineral oil or fire-resistant) to transmit power to where it’s needed for performing work. With time and use fittings can loosen, component performance diminishes and hoses wear and tear. In hostile environments, like coal mining, hydraulic hoses can fail in as little as 2 years according to DGUV (umbrella association of German Accident Insurers), maybe sooner in some particularly challenging environments. FLUID POWER SYSTEM SAFETY While appearing simple and benign on the surface, fluid power systems, particularly such systems on mobile equipment, have many potential hazards. Hazards that most workers aren’t aware of – particularly young, new hires. And those hazards that can quickly turn deadly. During the past couple of years, including at last year’s SME Conference, I talked to a wide variety of mining people about high pressure fluid injection injuries. Some people, often with little or no field experience, never heard of it. But, people with mine operations / maintenance experience were almost always aware of such injuries.Some had even seen it happen right in front of them. But most claimed it didn’t happen all that often. It just wasn’t seen as a problem!"

Jan 1, 2016

By J. M. Réjean Gagnon

"Quebec Cartier Mining Company is currently mining a low-grade iron ore deposit in northeastern Quebec. The Company is producing some 8,000,000 dry gross tons of concentrates per year, grading about 66 per cent iron. The pit, which is located on the keel or hinge line of a fold, will eventually be about 1,000 feet deep with a surface area of 8,000 by 2,600 feet. The most significant structural discontinuities in the mine are the natural bedding planes and secondary perpendicular joints. The exposed walls are subjected to a sub-Arctic climate and heavy blasting occurs approximately six times a month.QCM utilizes design and operating techniques to control rock fall. Steps are also being taken to analyze the ultimate over-all pit slope stability."

Jan 1, 1968

By R. E. Vivas, J. A. Villa

"Located in the state of Colima, Peña Colorada is one of the largest iron ore operations in Mexico. The project is owned in equal parts by ArcelorMittal and Ternium. Though boasting a production capacity of 4.1 Mt/a (4.5 million stpy) of concentrate per year, Peña Colorada is faced with declining ore grades. In order to respond to this situation, Peña Colorada had to expand production even further. This expansion created various challenges that were overcome by the adoption and application of new technology. Examples of these technological innovations are discussed in detail in this article and include improvements in geo-modeling, mine planning, and mine operations. The successful implementation of these technologies paid for itself many times over, and has led to significant improvements in production and performance, while lowering the operating costs and reducing the variance between planning and execution.Project overviewPeña Colorada is a mining company that produces about 30 percent of the iron ore in Mexico. This project generates about 1,200 direct jobs and 3,000 indirect jobs, making a significant contribution to the local economy. Similarly, Peña Colorada invests in its local communities through numerous educational programs, scholarships, university agreements, social development, environmental agreements, etc. Peña Colorada’s operations consist of an open pit mine located in Minatitlán and a pellet plant located in the port city of Manzanillo, as shown in Fig. 1. Technological innovationsMost mining projects around the world typically follow the logic of “mining the next best ore.” Consequently, head grades tend to decline over the life of the mine. In the case of Peña Colorada, a decline in head grade combined with a decline in iron ore prices forced the operation to adapt to a new business environment and adopt new technologies to face these challenges. However, the first step along this process was to increase the confidence and reliability of the resource model. This task involved additional drillhole campaigns coupled with more detailed modeling techniques. Once the block model was completed, new optimization studies and production schedules were evaluated with new optimization tools that improved many aspects of the mine plan. The Peña Colorada block model has undergone 3 expansions to reflect additional information not available in the past. The model has expanded to the East and Southwest. The latest model expansion increased the total number of benches to 98 as a result of positive exploration results. Similarly, new geotechnical studies were prepared, which provided new guidelines for pit slope design, and new technology was implemented to monitor ground movement and slope stability. Two sectional block model views in Hexagon Mining’s MineSight 3D, along with the pit designs and geologic solids are shown in Fig. 2."

Feb 1, 2017

By Mustafa Akser

The Pipestone Lake anorthosite complex in Manitoba, Canada, was recently been re-identified as a potential source for titanium, iron, and vanadium. The present study utilized a 350 kg hard rock sample, which originated from the "Main Central" zone of the deposit. Commercial pilot-size equipment, such as dry low intensity roll magnets, wet high intensity magnets (WHIMS), and high tension electro-dynamic roll separators, was employed. As products, ilmenite up to 48.5% TiO2, and magnetite concentrates up to 87.9% Fe3O4 with 5.25% TiO2 were obtained. The majority of the vanadium reported to the magnetite concentrate. Subsequent characterization of various separation products shed light on the potential grade and recovery of the minerals from this deposit.

Jan 1, 1996

By Michael D. Loy

This paper examines the computerization steps of United Coal Company of Bristol, Virginia. OVERVIEW Producing close to 7,000,000 tons per year, United Coal Company is one of the most interesting mining companies in the east. Their approach to mining reflects a dedication to modern technologies and extraction methodologies. With varying amounts of production coming from four divisions (a fair amount of production comes from contract operators) and over a billion tons in recoverable reserves, United rests heavily on the planning and engineering efforts of a centralized engineering group. Although each division relies on its own engineering personnel for day-to-day management and operations, long range planning and reserve management is conducted at the corporate engineering level. This group, while extremely competent and efficient, is relatively small (7 people), when compared to the needs of a large mining company.

Jan 1, 1985

By Seshadri Seetharuman

The present paper summarises a series of measurements of the interaction parameter of oxygen in liquid copper with respect to a third element, e(M)o, where M is Mn, Zn, As, Se or Te which are common impurities in the liquid metal. The technique employed was the solid electrolyte galvanic cell method. The cell used may be represented as Pt, W or cermet / Cu-O-M // ZrO2 - CaO // AO, A /PT where AO/A represents a suitable oxide/metal reference. The measurements indicate that Mn and Zn interact very strongly with oxygen in liquid copper while, in the case of arsenic the interaction parameter is nearly zero. The behaviour of the elements Se and Te is unique with respect to oxygen interactions in copper bath. At oxygen levels, xo= 10-4 ? 10-5, the apparent interaction parameters are negative, comparable to that for sulphur. On the other hand, at lower oxygen levels, the results indicate that the interaction parameter values are positive. The results are discussed in the light of some of the theoretical models for solute interactions in liquid metals.

Jan 1, 1993

By Chris Carr

This paper describes the process employed and the work undertaken to enable the surrender of the mine permit relating to the two tailings deposits at the abandoned Red Mountain Mine site near Rossland, BC. The first phase of the work undertaken was to provide urgent remedial work for protection of the environment, primarily through rehabilitation or replacement of surface water drainage systems. The second phase was to up-grade the water management systems to the appropriate level given their consequences of failure. The final phase of work is to ensure long term geotechnical stability of the facilities to the same level of risk. Establishment of a sustaining fund will facilitate long term monitoring and maintenance of the facilities.

May 1, 2002

By R. J. McNally

THERE are three primary plant nutrients—nitrogen, phosphorus, and potassium—expressed in any fertilizer compound as percent N, percent P 2 O 5, and percent K 2 O, in that order. This article will be concerned with the first two. The chief source of P 2 O 5 is phosphate rock. As found in the western states phosphate rock is essentially tricalcium phosphate-calcium fluoride (fluor-patite). As such, it is quite water insoluble.

Jan 1, 1957

By Takeo Fujino, Nobuaki Sato, Junichi Hasegawa, Masato Nakazawa, Kohta Yamada

"Tantalum oxide thin films were deposited on quartz substrates by laser ablation of Ta2O5 target using Nd:YAG pulse laser. Deposition-was observed when a laser light energy higher than 200 mJ and its repetition rate higher than 3 Hz. A thin film of 0.1 µm thickness was obtained by the ablation using a laser light of 300 mJ and 6 Hz for 2 sec. The thickness of the film increased with increasing energy, repetition rate and irradiation time of laser. By the SEM observation, it was found that many island-like particles were deposited on quartz substrate forming a thin film. The obtained thin film, which was identified as ? Ta-O by X-ray diffraction, was oxidized to Ta2O5 by the heat treatment in air at I273 K for 3 h.IntroductionTransition metal oxides have a potential to show special characteristics in electrical, magnetic and/or optical properties. When such compounds are fabricated in the form of thin film, the special properties would be improved or new characters would appear in comparison with bulk materials. Tantalum penta-oxide is widely used as a capacitor since Ta2O5 shows high dielectric constants up to high temperatures. The tantalum solid capacitor has been fabricated by the electrical oxidation of sintered Ta metal cylinder followed by MnO2 film coating. However, further improvements, reduction and layered structure formation, are required for compacting the devices. The layered structure of thin films would be applicable for the above requirements. The formation ofTa2O5 film by low pressure CVD1), photo CVD2) and magnetron sputtering3l were reported. The laser ablation -method is one of the most convenient techniques for the deposition of thin films from their compounds, such as oxides. Formation of Ta2O5 film by pulse laser deposition (PLD) method using ArF excimer4), Nd:YAG (533nm)5) and TEA CO2 6 lasers was reported. In these PLD studies, ablation was carried out in relatively high oxygen pressures resulting in formation of Ta2O 5 film. In this paper, the deposition of tantalum oxide thin film by the laser ablation of Ta2O 5 using Nd:YAG pulse laser was examined at a viliety oxygen pressures ranging from 10-8 to 10 Torr. The morphology of the films was also investigated in relation with substrate temperature and oxygen pressure."

Jan 1, 2000

By J. Chen Kuriyama

One method to store hydrogen effectively involves the use of metal complexes such as the alkali-element aluminum hydrides. The hydriding/dehydriding properties of these materials depend on how to prepare them with different structures and microstructures. The present work focused on a high-energy ball milling technique to produce Ti-doped lithium tetrahydridoaluminate (LiA1H4) and lithium hexahydroalanate (Li3AIH6) powders with nanocrystallites. The phase structures and dehydriding/rehydriding characteristics were investigated by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Brunauer-Emmett-Teller measurement, thermogravimetry, and differential scanning calorimetry. The mechanism of dehydrogenation and rehydrogenation was also examined by means of X-ray photoelectron spectroscopy (XPS). The results on the relation between the reversible hydrogen storage and catalysis function of the Ti-doped complex hydride indicate that both the homogenous distribution of Ti+AI nanoclusters and the Ti¬catalyst with Ti e> Ti3+ (Ti0/Ti2+/Ti3+) defect sites play important roles in optimizing the reversible hydrogen storage.

Jan 1, 2002

By J. E. Wilson

A bench-scale expansion tester using 71 grams of coal was developed to determine the practicability of an apparatus of this size to investigate the effect of variables such as oxidation, blending, bulk density, inerts, size consist, petrographic differences, and rate of heating on the expanding properties of coal. The value of this tester is shown by the correlation that exists between its results and those of the larger scale sole-heated oven expansion apparatus used in commercial plants. From tests on 32 coals the standard error of estimate for predicting sole-oven results from bench-scale results is ± 5.3 percentage points. A standard deviation of the difference between pairs of tests in the latter apparatus of ± 2.1 percentage points was determined for 31 samples. In the sole-heated oven test the expansion of a coal at constant pressure is directly proportional to the dry coal bulk density. Tests in the bench-scale tester show a similar relationship between expansion and bulk density. When the blending ratios of high-and low-volatile coals are varied, similar changes in expansion are observed in both the sole-heated oven and the bench-scale tester. Therefore, the effect of other variables on expansion should be similar in the latter apparatus.

Jan 1, 1960

By S. R. Stine

The Cyprus Thompson Creek Mine is located at 2,286m (7500 feet) elevation in the Central Idaho mountains, 61.16 kilometers (38 miles) southwest of Challis, Idaho off State Highway 75. The Thompson Creek molybdenum deposit lies near the eastern border of the late Cretaceous Idaho Batholith within a complexly deformed sequence of Paleozoic sedimentary rocks. Molybdenum mineralization is contained in a composite biotite granodiorite-quartz monzonite stock considered to be genetically related to the Idaho Batholith intrusive event. The ore is being mined by open pit methods and delivered to the concentrator stockpile with an overland conveyor belt system. The concentrator is designed as a 22,680 metric tons (25,000 ton) per day plant at an average head grade of 0.1% Molybdenum.

Jan 1, 1986

By Jr. D'Angelo, Michael M. Blendy, Shawn Downey

"A grouted helical pile was used to support new buildings in the reconstruction of a large residential development. Foundation options were complicated by urban fill underlain with variable alluvial soil. A driven timber pile and grade beam system was recommended to support the new buildings. Other foundation options are also discussed. The grouted helical pile was quoted as an alternate and ultimately won the bid based on the economics and performance of the system. Data from 8 load tests was used to develop an empirical site specific relationship for determining pile capacity based on both installing torque and installation depth. Design to incorporate tolerance on installed pile location is presented. With the three phases completed, 554 residential dwelling units supported by 3645 grouted helical piles had been constructed covering 18 city blocks on the 44 acre site. IntroductionThe Philadelphia Housing Authority reconstructed the Tasker Homes housing complex located in southern Philadelphia, Pennsylvania, adjacent to the Schuylkill Expressway in the Grays Ferry area. Keating Building Corp. and Pennoni Associates were the general contractor and the structural engineer respectively. The original Tasker Homes development was constructed from 1940 to 1941 and consisted of 44 acres of primarily two and three-story residential brick buildings. These buildings were supported by a timber pile foundation system. The structural condition of the buildings supported on the timber piles was generally good in comparison to areas outside the buildings. These areas had settled possibly up to 2-feet in places due to the heterogeneous nature of the urban fill."

Jan 1, 2005

By D. Neuschiltz, M. Witthaut, R. Cremer

"Metastable (Ti,Al)N coatings with fee structure have been shown to exhibit superior performance as compared to TiN under conditions of wear at elevated temperatures due to their better oxidation resistance and hardness. The oxidation resistance of these coatings increases significantly with increasing Al-content. However, the deposition of (Ti,Al)N films with Ti/ Al ratios below about 30/70 leads to a hexagonal structure which is not suitable for tribological coatings. Only little is known about the location of the cubic to hexagonal phase transition and hence about the optimum composition of (Ti,Al)N hard coatings.To determine the position of this transition, Tii-xAlxN films with different Ti/Al ratios were deposited on high speed steel at substrate temperatures between 100 and 700 °C by means of reactive MSIP. The composition of the films was determined by electron probe microanalysis (EPMA) and X-ray photoelectron spectroscopy (XPS), the crystallographic structure by thin film X-ray diffraction (XRD).It could be shown that in case of deposition temperatures of 300-700 °C a two-phase region exists in the metastable TiN-AlN phase diagram, which expands with increasing temperature, wheras at 100 °C substrate temperature no two-phase region was observed. But in opposition to the phase diagram known from literature, which is based on thermodynamic estimations, the detected two-phase region is narrow for typical PVD temperatures, thus allowing the deposition of cubic single-phase Al-rich (Ti,Al)N hardcoatings for tribological applications. Based on these results, a new Ti1-xAlxN film with x = 0.62 has been developed, which showed an increase of oxidation resistance by a factor of 4."

Jan 1, 1998

By K. Chandrasekaran

Carbon-in-Leach (CIL) is conventionally used in gold processing operations when preg robbing components are present in the ore. CIL process is becoming attractive even in other situations when preg robbing is not a factor. This paper discusses the situations in which the CIL circuit can be applied. The results of Leach/CIP and CIL circuits at Newmont's Mill No.2, 4 and 5 are presented for comparison. Newmont's Mill No. 4 was initially designed for a throughput of 4500 tons per day. The mill is presently operating at an average throughput of 7300 tons per day without significant changes to the original design. The design considerations of the Mill No.4 CIL circuit are discussed.

Jan 1, 1991

By Dan Miners

"This presentation will provide an overview and understanding of Mine Safety and Health Administration (MSHA) and Ontario Regulations for Mines and Mining Plants. It includes discussions on the history and practical development of the standards and an overview of engineering best practices from a construction, maintenance and operational viewpoint. INTRODUCTION Ontario is one of the safest mining jurisdictions in the world and has some of the most comprehensive regulations for the construction, operation and maintenance of a mine. In the USA, several operators have adopted some or all of the practices prescribed by the Ontario Regulations as an internal procedure. Experience has demonstrated that these plants are indicating less unplanned downtime and fewer issues with MSHA inspectors in their hoist plants. HISTORY AND THE REGULATIONS Both Canada and the USA have had some form of laws governing the operation of mines since the late 1890s. The paths of legislation have run in reasonably parallel lines, continually improving the health and safety conditions in the mining industry. Ontario Mine Health and Safety In the 1970s the accident rates in mining were higher than any other industrial sector; this prompted a Royal Commission on the Health and Safety of Workers in Mines (the Ham Report). The recommendations of this report, published in 1976, generated several changes in the regulations regarding worker safety in mines. Following the release of the Ham report, the Occupational Health and Safety Act (OHS) was passed by the Legislature in 1978. The Act is a set of comprehensive laws governing almost all Ontario workplaces, and it replaced separate laws governing different industrial sectors. OHS is enforced by the Ministry of Labour (MOL), and this discussion will focus specifically on Ontario’s Occupational Health and Safety Act, R.R.O. 1990, Regulation 854, Mines and Mining Plants, Part X Mine Hoisting Plant (Ontario Regulations). USA Mine Health and Safety A coal mine explosion in West Virginia and medical studies on occupational disease led to the 1969 Federal Coal Mine Health and Safety Act (Coal Act). The Coal Act was the most comprehensive and stringent Federal legislation governing the mining industry to date. The Mining Enforcement and Safety Administration (MESA) was formed, following the 1973 Act, as a new departmental agency to assume the enforcement of safety and health in mines. The Federal Mine Safety and Health Act of 1977 (Mine Act) transferred enforcement responsibilities from the Department of the Interior to the Department of Labor and named the new agency the Mine Safety and Health Administration (MSHA). This agency enforces the Code of Federal Regulations (CFR), and this discussion refers to CFR Title 30 Mineral Resources, Chapter I Mine Safety and Health Administration, Department of Labor, Subchapter K—Metal and Non-metal Mine Safety and Health (MSHA)."

Jan 1, 2019

By K Karmawan, T Casten

The PT Freeport Indonesiaæs Deep Ore Zone (DOZ) copper deposit is located in the province of Irian-Jaya, Indonesia. Currently, a block cave mine is being developed around this deposit. Production is scheduled to start the fourth-quarter of year 2000 and to ramp up to 25 000 tpd by year 2003. The air quantity requirement for this mine is equal to 780 m3/s. To supply this quantity, the mine will require five centrifugal fans (one 450 and four 750 kW fans). This study summarises the technical aspects related to the installation and commissioning of two of these fans. The fans were installed on the surface in parallel arrangement with two others. Each has a design capacity of 240 m3/s of air at 2.2 kPa of static pressure. The study presents the installation details from the underground shaft excavation and portal development through fan testing and commissioning. It also presents the results of a monitoring system that was installed to determine the fan duties.

Jan 1, 2000

By Nikzad Oraee, Parham Khajehpour, Kazam Oraee, Arash Goodarzi

"Rock fall related accidents continue to occur in coal mines, although artificial support mechanisms have been used extensively [1]. Roof stability is primarily determined in many underground mines by a limited number of methods that often resort to subjective criteria. It is argued in this paper that stability conditions of mine roof strata, as a key factor in coal mines, must be determined by a survey which proactively investigates fundamental aspects.Failure of rock around the opening happens as a result of both high rock stress conditions and the presence of structural discontinuities. The properties of such discontinuities affect the engineering behavior of rock masses causing wedges or blocks to fall from the roof or slide out of the walls [2]. A practical rule based approach to assess the risk of a roof fall is proposed in the paper. The method is based on the analysis of structural data and the geometry and stability of wedges in underground coal mines. In this regard, an accident causing a huge collapse in a coal mine leading to four fatalities is illustrated by way of a case study. A comprehensive investigation of the hanging wall has been gathered through a systematic collection of evidence. The investigation results are then analyzed, and an interpretation of the evidence gathered is provided.For this purpose, horizontal and vertical profiles are prepared by geophysical methods to define the falling zone and its boundaries. The collapse is then modeled by the use of sophisticated computer programs in order to identify the causes of the accident and hence recommend corrective actions to prevent or minimize reoccurrence probability of similar accidents. The corrective measures are placed into a rule-based framework for the benefit of the mine operators.INTRODUCTIONRoof rock failure has generally been the most dangerous hazard for underground coal mining in the world. Failure of rock around shallow coal mine openings often results from loosening of blocks of rock on the weakened planes under the influence of gravity. This condition is not typically seen in large deep coal mines. There are a number of differences between large mechanized mines and small mines related to ground control [3]."

Jan 1, 2015