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By Daniel Mallette, Richard Goodridge, C M. Lownds

Despite a world of mobile devices that has many of us taking the ability to communicate wirelessly for granted, an in-hole wireless initiation system was thought to be not viable. The known and common wireless communication techniques are not suited to this application. To overcome this, we have developed cutting edge technology to communicate to our initiating devices more than 1km through solid rock.

Jan 1, 2016

By P. S. Heyns, M. Heyns

A computer model has been developed of mine hoisting systems in deep South African gold mines. Particular attention was paid to the contribution of different modelling assumptions for the guides and guide-roller assemblies. Objective functions indicative of guide-roller tyre endurance, slipper-plate forces and perceived vibration levels were introduced to quantify dynamic performance. These objective functions were used to compare models. It was found that the choice of guide and guide-roller models did not influence the forces on the guide rollers significantly for typical shaft and conveyance characteristics at typical levels of viscous damping coefficients. The rigid and finite-element guide models gave the same results as those of the effective-stiffness guide model, and while the latter is suitable for simulation for design purposes, the finite-element model should be used for unusual guide geometries

Jun 19, 1905

By Richard Mcivor, Largo Albert

"Inco Limited has operated aluminum mine shaft conveyances since 1968. Aluminum conveyances are used where the hoisting in system requires lightweight conveyances to maintain the hoist rope safety factors and mine hoist rope pulls as dictated by government regulations. Inco Ltd. currently has 20 skips (including spares) operating in the Ontario Division mines. The main problems encountered are with galvanic corrosion between dissimilar metals and metal fatigue. This paper will highlight some of the problems encountered and illustrate methods utilized to overcome the problems and improve the conveyances performance.IntroductionAluminum mine shaft conveyances have been in use at Inco Limited's various Sudbury district mines since 1968. All of the conveyances currently in use are skips used for hoisting mine ore and rock. Inco had an aluminum quick change Kimberley-type skip and cage in operation at its Totten Mine in the early 1970s, but this mine is no longer in operation and no further comment will be made.The primary reason why aluminum conveyances are chosen over conventional steel conveyances is because of their light weight. Typically an aluminum conveyance will weigh about 60% to 70% of a steel conveyance of similar design. The lighter weight conveyances will allow higher payloads to be used and still maintain the statutory hoist rope factors of safety. It must be remembered that increasing the payload will increase the power required to raise the load and the hoist will have to have the necessary horsepower for the increased payload or the system will be overloaded.The front dump (Rola-chute) skips are of the bail-less design, i.e. the box structure also supports the load and has the shaft guide shoes attached directly to the side of the box structure. The Copper Cliff North Mine and South Mine skips have a joint in the centre of the conveyance and are installed in the shaft in two sections and connected with pins. This feature allows very long (42 ft) skips to be used in areas where a one-piece bail-type conveyance could not be installed. It is not practical to make sectionalized bail-type conveyances"

Jan 1, 1988

By J. X. Wu

An investigation on the seismic damage to buildings with pile foundations in Tianjin region, was conducted after the earthquake which hit Tangshan in 1976. It showed that most pile-founded buildings have an excellent aseismic capacity. In this paper, several pile-founded projects suffering the seismic damage are introduced as examples, simplified calculations are made of the vertical bearing capacity of pile foundations and of the horizontal seismic force, and suggestions are presented in conection with the design of pile foundations in the liquified ground soil. The paper shows a frame structure which has a plie foundation with a box-shaped base. Analyses if its response to the earthquake has been carried out in accordance with the F.E.M. and results have been obtained.

Jan 1, 2010

By J. S. Miller

This report presents a complete coverage of results from Bureau of Mines preliminary research and the field application of explosive fracturing techniques to prepare oil shale for in situ recovery of shale oil. Small-scale surface tests were conducted to determine the feasibility of using a nitroglycerin-base explosive for creating rock fractures. Prior to underground testing, surface and near-surface tests with liquid explosives showed that explosions in sheetlike layers simulating underground fractures would propagate effectively. Successful surface experiments were conducted using layers of explosive placed between glass plates and explosive-saturated sand confined in small-diameter metal tubes. The tests in glass-plate reservoirs and metal tubes demonstrated that nitroglycerin would detonate and the explosion would propagate in cracks as thin as 1/32 inch and through distances up to 12 feet. In a shallow field test, nitroglycerin was detonated in a vertical crack in limestone and produced extensive fracturing. Explosive fracturing tests were performed in oil shale formations on seven sites near Rock Springs, Wyo. The procedures included (1) displacing and detonating nitroglycerin in natural or hydraulically induced fracture systems; (2) detonating nitroglycerin in wellbore shots; (3) displacing and detonating nitroglycerin in induced fractures followed by wellbore shots using pelletized TNT; and (4) detonating wellbore charges using pelletized TNT. The research on oil shale formations demonstrated that nitroglycerin displaced in a natural or hydraulically induced fracture would detonate, and the explosion would propagate through the explosive-filled fracture. Shooting a pattern of wells in oil shale at 100-foot depth with wellbore charges of pelletized TNT developed a satisfactory interwell fragmented zone. Tests performed on other sites at depths to 385 feet caused fragmentation of rock around the wellbore and provided interwell communication. Fourteen methods used to evaluate the extent and degree of fragmentation in the explosive fractured oil shale are discussed.

Jan 1, 1974

By Steve Kral

The mining industry is no stranger to hard times. Throughout its history, the industry has faced the ups and downs of commodity prices, difficult-to-mine-and-process ore bodies, labor issues and other problems. Throughout it all, though, the mining industry continues to provide the materials needed for society —even in the face of attacks by those who seek to cripple the industry or have it go away. The reason the mining industry survives, of course, is that mankind requires the products the industry produces. And, in recent decades, the industry has developed new technologies and improved on existing ones to produce those products in environmentally sound ways. At the same time, the economic benefits have been enormous to communities throughout the world where mining takes place.

Jan 1, 2002

By Donald Koch

The project investigated regional impacts of mining on the ground water system of the Powder River Basin by: 1) establishment of a regional ground water monitoring network, and 2)development of , set of digital computer models to simulate ground water flow and quality, ground water contributions to surface water flow and quality (i.e., baseflow), and watershed run-off and recharge. Over 100 wells were monitored for physical and chemical parameters. Data were used as input to the model; and for the development of a comprehensive data base. The basin was modeled on a regional and subregional scale using a finite -difference model employing an alternating difference technique. Two water-shed models were evaluated for their ability to provide runoff and recharge inputs to the basic ground water model. Application of the regional and subregional models using conservative mining scenarios showed that drawdowns may extend west from the mines as far as ten miles but that impacts would be insignificant on a regional scale. The watershed model could be effectively applied to small watersheds only.

Jan 1, 1982

By Dziurzyn&apos, W. ski

This article outlines the results of a computer simulation reproducing the transport of a mixture of air and methane following the outburst on 25 November, 2005 in transport gallery D-6, bed 409/4, at the ?Zofiówka? hard coal mine. Based on a mathematical model, numerical method and boundary conditions from the disturbance caused by the outburst, the Ventgraph system of computer simulation programs was adopted for the study. We performed a computer simulation of the influence exerted by the outburst on the propagation of the air and methane mixture, and compared the results of this simulation with those of the actual event as registered by sensors of the mine monitoring system. A validation of the model allowed us to present temporal changes in the concentration of methane and air along flow routes. Keywords: mine ventilation, outburst of methane, numerical simulation, monitoring system.

Jan 1, 2008

By William H. Dresher

Introduction A subject long debated but rarely resolved involves the interaction between the academic community and industry in the sponsorship and conduct of research. The subject is, unfortunately, too often treated as a controversy involving ethics and the profit motive. But, in fact, the two branches of society - industry and academia - are necessarily part of the same system. In the last 25 years, the realization has developed that research alone is not sufficient to bring about use of those results to benefit society through productivity gains and economic growth. The flow of events shown in Fig. 1 was generally believed to be the steps required for reaping the benefits of research. Today, research still has the very important role of creating new information or new ideas. However, it is recognized to be but one of many steps in a process that we now refer to as technological innovation. Charpie (1967) said, "Technological innovation is the driving force behind economic growth in the US. In this context, innovation means the process by which a new idea is successfully translated into economic impact within our own society, by providing better products, and simultaneously creating new jobs in the manufacturing of those products. Only after an investigation is put into sufficient use to have an economic effect, is it termed an innovation." One of the best depictions of the technological innovation process is shown in Figs. 2 and 3. These are adapted from Haeffner (1975), and modified by the Committee on Mineral Technology of the National Research Council (1981). Figure 2 identifies the many steps involved in the process. It designates a generalized form for interaction between the academic community and industry. Figure 3 identifies the steps in the "innovation activity" box of Fig. 2. Academia is generally responsible for developing of new knowledge and ideas, as well as maintaining and enlarging the collected body of scientific knowledge. Industry is responsible for developing new products, methods, and processes. Both institutions operate for the benefit of society, but under different driving forces. In academia, the driving force is the achievement of academic excellence. In industry, the driving

Jan 10, 1984

By V. Osterholt

Sustainable development of mineral resources is based on a spatial model of the orebody that is only partly known from exploration drilling and associated geological interpretations. As a result, orebody models generated from the available information are uncertain and require the use of stochastic conditional simulation technique. This paper considers three methods for simulating orebody geology: (1) pluri-Gaussian simulation that limits the allowable contacts between the various units; (2) sequential indicator simulation using indicator kriging; and (3) an experimental multiple-point approach that captures some higher-order spatial statistics. The data requirements of the methods, how to meet them in mining applications, and performance characteristics are discussed. The application of these methods in a hypothetical deposit consisting of three geological units provides a comparison and illustrates the advantages of the different simulation approaches.

Jan 1, 2005

By D. E. Pollock, J. A. Organiscak

Water sprays and water powered scrubbers have both been utilized in the mining and milling industry to suppress airborne dust. Unconfined water sprays operated at lower water pressures of ?689 kPa (?100 psig) can be very effective at wetting the mine product at the dust source and significantly reducing the amount of respirable dust that becomes airborne. However, unconfined waters sprays can be somewhat ineffective in actually removing airborne dust from the air. On the other hand, water powered scrubbers operating at higher water pressures of ?1,724 kPa (?250 psig) in physical enclosures or ducts have previously been demonstrated to be very effective in removing airborne dust from the air. These higher operating water pressures are uncommon in many mines and mills, so their use is limited. The National Institute for Occupational Safety and Health (NIOSH) recently investigated the performance of a lower-pressure, water powered inline series spray scrubber for removing localized airborne dust emitted at the source. Results showed noticeable improvements in airborne dust capture efficiency through the operation o f multiple inline series hollow cone spray nozzles within a round duct or pipe at the same water pressure as a single spray. Operating hollow cone spray(s) at higher water pressures noticeably improved airflow through the scrubber and yielded some additional scrubber efficiency improvements. Thus, in-line spray scrubber efficiency trade-offs were observed to be made by altering spray power components of water pressure and/or quantity (number of sprays). Results show that, on average, up to 0.23 and 0.32 m3/s (484 and 679 cu ft per min) of airflow at 0.81 and 0.69 dust capture efficiencies can be achieved with three 81° and 33°hollow cone inline series sprays, respectively, operating at 1,655 kPa (240 psig).

By William A. Beck

The Construction Aggregates Corp. operates a plant for processing sand and gravel from two deposits in Ottawa County, Mich. The bulk of the sand is obtained from a sand dune on the shore of Lake Michigan, and the gravel is dug from a glacial-drift deposit farther inland. Mining is done with draglines, and the material, both at the digging site and in the plant, is moved mainly by systems of conveyors. The Ferrysburg plant serves customers along the Great Lakes, which is unusual for a business normally local in character. Annual production exceeds 1-1/2 million tons of sand and gravel as concrete aggregate and 200,000 tons of core sand for foundry use.

Jan 1, 1962

By Nicholas G. Theofilos

The only mining activity in Belize during 1976 involved the production of construction aggregates, which were used domestically. A comprehensive ordinance regulating mineral prospecting and mining was proposed during the year. Under the ordinance, which would supersede all grants and titles, ownership and control of all minerals except petroleum would be vested in the Government. Exxon Corp. entered into an agreement with three oil companies to achieve a majority interest in nine oil prospecting leases covering 1 million acres, mostly offshore Belize. The agreement was with Weatherford International Inc. which had 30% interest in the leases, Ajax Petroleum Co. with 40% interest, and Canadian Superior Oil Ltd, with 24% interest. A new entity, Esso Ventures Inc., was established to be responsible for conducting extensive geophysical operations and drilling an exploratory well offshore Belize.

Jan 1, 1980

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Jan 1, 1994

By A. George Stern

In the examination of bentonitic clay suspensions used for oil-well drilling fluids3/ (and for other purposes, such as a core binder for foundry sand) it is important to have comparative tests for evaluating them. A satisfactory clay for these and other purposes should 'rave the property of forming what is commonly called a "gel," but the measurement of this property has been a real problem. To date the solution has not been satisfactory, and some of the difficulties are considered in, this, paper, which describes a simple form of instrument (identified as an eykometer) for measuring the yield point under hydrostatic conditions of non-Newtonian clay suspensions, including those muds that are thixotropic. An oil-well drilling mud serves several functions, many of which depend on the "gel" characteristics of the mud. Among the more important functions are: (a) To plaster the sides of the hole to prevent caving of the walls; (b) to prevent the loss of the circulating fluid out of the hole by seepage; (c) to carry sand and cuttings out of the hole to the surface as they are formed by the rotary drill; and (d) when circulation of the fluid stops for shut-down or other unavoidable cause, to hold the cuttings in suspension by the setting up of the gel, thereby avoiding the difficulties that result when these cuttings are allowed to fall through the fluid and pack at the bottom of the hole.

Jan 1, 1940

By Robert Harris, Peter Pheeney

"The Murray Brook gold mine operated from September 1989 to March 1991. Approximately 1.2 million tonnes of gossan were mined from an open pit and treated at a rate of 900 tonnes per day. The facility applied an agglomeration vat-leaching cyanidation plant for gold and silver recovery. The leached ore or tailings were rinsed of residual gold and cyanide and placed on an adjacent clay lined pad for storage and containment. A 50,000 tonne heap-leach demonstration project was constructed at Murray Brook in 1992 to recover copper and zinc from ore located in a sulfide-rich zone occurring beneath the gossan. The operation proved unsuccessful because of poor recoveries and low metal prices. The project terminated in the same year.A corporate decision was made in September 1999 to undertake complete and final reclamation of the Murray Brook site. Jacques Whitford and Associates Limited were contracted to develop the final reclamation plan and to assist the company in presenting the plan to the New Brunswick government for approval. The government approved the plan in January 2000. Two important reclamation issues were the mobility of mercury from the gossan tailings and the potential of acid mine drainage from exposed sulfides. The mine site is situated upstream of a productive river system, and the issue or impact of chemistry changes to the environment over the long term became an overriding factor in the development of the reclamation plan.A resource assessment of the gossan tailings in 1999 indicated an average concentration of mercury of 40 ppm. The mercury occurred naturally as the mineral cinnabar, but the exposure to residual cyanide (less than 10 ppm) over several years in the pile has likely caused much of the cinnabar to decompose into more soluble mercury forms. The reclamation plan specified the replacement of all sulfides to the pit followed by approximately 600,000 tonnes of gossan. To ensure “fixing” of the mercury, the gossan was replaced in compacted lifts and both the remaining pile and that replaced to the pit covered with available till and compacted. The reclamation work was successfully completed in September 2000 and the chemistry of the receiving environment will be monitored over a three-year period, after which the company expects to achieve walk away conditions."

Jan 1, 2001

By Mikhail P. Nesterov

The paper presents the results of the research that can forecast the development of subsidences and deformations of the earth surface with time in the permanent marginal areas of the movement troughs arising when mining sylvinite beds in the Upper Kama deposit of potash ores where the rock formation support is made by means of interchamber (rib) pillars of various yieldability.

Jan 1, 1997

The French research institute, INERIS, requested the assistance of the CSIR?s Division of Mining Technology in developing further precautionary measures against explosions in their collieries. In response to this approach, an on-board active suppression system was adapted to meet their mining requirements. This system is used on tunnelling machines in Germany where the machine is positioned in the middle of the tunnel, which is therefore not much wider than the machine itself. With this configuration, the machine is never away from the tunnel face during the cutting cycle. As a result, the possible volume in front of the machine of combustible gas requiring suppression is less than 50 m3. In South Africa this technology has been adapted to suit a two-cut mining method which entails greater distances from the face and thus much larger volumes of methane mixtures requiring suppression. The particular configuration of the Explo-Stop® system being investigated required the suppression of possible methane ignition volumes of up to 180 m3of a 9% per volume methane/air mixture. The volume is a consequence of the large cross-sectional area of French underground workings and of the two-cut mining method used in France. In order to take the second cut in the coal seam, the machine is pulled back a maximum distance of 4 m, leaving an air pocket in which gas can accumulate. The machine-mounted system is required to effectively suppress any flame ignited by such a large accumulated volume of methane. The results of the protocol tests done at Kloppersbos showed that the system was capable of suppressing all simulated methane ignitions for the prescribed conditions. This was achieved with a temperature increase of less than a 100°C at the operator?s position and without any flame being detected at this position.

Jan 1, 2001

By Misra V. N, Cheng C. Y

Two types of Mt Tom Price hematite iron ore from Hamersley Iron P/L were tested using a Humboldt Wedag Jones P40 wet high intensity magnetic separator (WHIMS). The parameters tested were magnetic intensity (7000, 9000 and 11 000 Gauss), groove plate type (8R and 12R) and gap width (2.5 and 1.8 mm). It was found that at 9000 gauss magnetic intensity, reasonably high-grade and recovery in the concentrate were obtained. At 2.5 mm plate gap width, the 12R groove plate performed slightly better than the 8R groove plate. Further testwork is recommended to optimise the magnetic intensity, feed flowrate and pulp density, wash water pressure and flowrate with 12R and 8R groove plates at 2.5 mm gap width.

Jan 1, 1999

By Janet A. Flinn, David G. Fileccia

Machine guidance and control systems have become more pervasive in the mining industry in recent years but not always from mining-experienced providers. Dozers, motor graders, scrapers, excavators, shovels, draglines, drills and haul trucks are just a few examples of the types of heavy machinery now equipped with global positioning system (GPS)-aided guidance systems. While equipment manufacturers are offering their own software, many only supply solutions for the machines they produce. The proliferation of GPS equipment manufacturers entering the machine guidance and control arena has resulted in a multitude of makes and models of GPS receivers. Some of these companies also produce their own guidance software. But they usually just specialize in a narrow range of heavy machinery. So customers are forced to use multiple systems and face new challenges in implementation, training, reporting and inter-system communication.

Jan 1, 2006