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By Batric Pesic

Recovery of gold from refractory ores was studied by pressure oxidation as the method of ore pretreatment followed by bromination of oxidized residues. Three different ores were examined, Au-Ag, Au-Ag-Te, and Au-silver free ore. Pyrite was the major host mineral for gold in these ores. The effect of pressure oxidation parameters (temperature, pressure of oxygen, time, and pulp density) on subsequent bromination under standard conditions was examined. Bromination of residues produced under standard pressure oxidation conditions was examined as a function of: temperature, bromine and sodium bromide concentration, and time. Recovery of gold on activated carbon, from the pulp after bromination, was studied too. Recovery of gold from silver containing ores was lower (87-91%) than the recovery of gold from silver free gold ore (97%). In each studied case, the presence of activated carbon in the pulp further increased the recovery of gold.

Jan 1, 1992

By Yong .. Jun Wu

Laminated ceramics have received widely scientific and commercial attention because their properties, such as mechanical properties and electrical properties, can be tailored by adjusting the structure, thickness and composition of the different layers. For example, ferroelectric Bi4Ti3O12 (BIT) which has a positive temperature coefficient of dielectric constant (,E) can be used to modify the negative tE of typical microwave dielectric ceramic BaNd2Ti4O12(BNT), However, BaNd2Ti4O12/Bi4TiO12/Bi4Ti3O12/BaNd2Ti4O12 (BNT/BIT/BNT) laminated ceramics could not be prepared by the general method because the optimal sintering temperature of BaNd2Ti4O12 ceramic (around 1350°C) was much higher than that of Bi4Ti3O12 ceramic (around 1100°C). In this research, a new method of spark plasma sintering (SPS) combined with post-sintering was successfully proposed to prepare BNT/BIT/BNT laminated ceramics. It was divided into three steps. In first step, the BaNd2Ti4O12 ceramics were prepared by conventional sintering method. In second step, the calcined and pre-pressed Bi4Ti3O12 powders were sandwiched between BaNd2Ti4O12 ceramic pellets and spark plasma sintered at 900°C for 10min to synthesize BNT/BIT/BNT composite ceramics. In the last step, a post-sintering was employed to reoxidize the partially reduced BNT/BIT/BNT composite ceramics. The results of scanning electron microscopy (SEM) and electron probe microanalysis (EPMA) showed that BNT layer and BIT layer were well bonded and no significant interfacial infiltration between them was observed. The sandwiched BNT/BIT/BNT ceramic with 10.7% BIT in volume has a dielectric constant of 92.85, a low dielectric loss of 01068 and a small temperature coefficient of dielectric constant of 35 ppm/°C at MHz.

Jan 1, 2003

By E. D. Calvert

The room temperature tensile properties of commercially pure titanium and seven titanium alloys prepared by skull casting were determined in the as-cast and heat-treated conditions. Data were compared with property data from tensile tests on wrought alloys of the same compositions in the as-worked and heat-treated conditions. The alloys evaluated were Ti-5Al-2.5Sn, Ti-6Al-4V, Ti-6Al-4V-lSi, Ti-6A1-2Sn-4Zr-2Mo, Ti-6A1-6V-4Zr-4Mo, Ti-6A1-6V-2Sn, and Ti-11.5Mo-6Zr-4.5Sn. Test specimens were prepared from both static and centrifugal castings and from plate fabricated by forging and rolling vacuum-melted ingots. The data indicate that the alpha and alpha-beta alloys have strength properties in the as-cast condition that are reasonably close to the strength properties of their wrought counterparts in the as-worked condition. An exception to this was the Ti-6A1-6V-4Zr-4Mo alloy for which insufficient data were available to form any firm conclusions. Fine-grained cast structures of Beta III (Ti-11.5Mo-6Zr-4.5Sn) were shown to be generally stronger in the as-cast condition than the wrought alloy in the as-worked condition except for the yield strength of one structure that was unusually low. Heat treatment of this alloy produced properties that were unpredictable. Indications are, however, that optimization of heat treatment parameters for each cast structure could produce strength properties equal to that of wrought materials.

Jan 1, 1974

By J. S. Aronofsky

The areas are identified where the techniques of operations research have been applied in the petroleum industry. Particular emphasis is given to the linear program models that have been used for solving management problems. Of the entire gamut of applications for linear programming, attention is focused on the models that represent underground reservoirs. Such models could be used to help schedule drilling rig operations and to schedule oil production. A framework is established for placing the model for underground reservoirs in the proper perspective along with the models which represent other facets of the oil business. One of the remarkable phenomena of this century is the rapid growth in the size and' complexity of human organizations. The mere size of modern business means that administrative decisions can affect vast quantities of capital and large number of people. Mistakes can be tremendously costly, and a single wrong decision can require years for rectification. Moreover, the pace of modern business is such that decisions are required more rapidly than ever before; the mere postponement of action can give a decided advantage to a competitor. It is not surprising that the increase in difficulty of decision making has been followed by efforts to put this activity on a more objective basis. The growing science of operations research, which relies heavily on the methods that have proved so successful in the physical sciences, is one aspect of these efforts.

Jan 1, 1962

By Frederick T. Williams

THE purpose of this paper is to discuss the relative merits of the large 31/8 in. machine and the small 21/4-in. tappett machine in driving development-headings ; and although the . data here presented were obtained from cross-cut headings alone, experience has shown that the results are equally true in drifting, raising and winning. Recently we drove two parallel cross-cuts through the same formation, using a 3k-in. machine at the breast of one cross-cut., and a 2k-in. machine of the same make at the breast of the other. The results of this work afforded an ideal comparison, since in both cases the headings were advanced through rock practically of the same hardness and breaking-properties ; the amount of sludging was equal, and there was no difference in the condition of the steel or the machines, in the air-pressure or in the experience of the operating-crews. Some operators in the Cripple Creek district contend that there is ground which cannot be handled with the small machine, the holes being too small to contain enough powder to pull the ground, etc. The results obtained in working the property of the Portland Gold Mining Co., however, show that the ground worked by them does not fall in this class. During a period of two years there have been driven, with the small machine, 4 miles and 308 ft. of development-headings, through a diversity of ground, including Pike's Peak granite (a coarsely porphyritic type of granite), highly indurated, andesitic or phonolytic breccia, true massive andesite, trachytic phonolyte, tuffas, and along dikes of decomposed basalt and hard phonolyte; in every instance a satisfactory record was made. The headings here described were driven through highly indurated, andesitic breccia, having a hardness of from 5.2 to 7.2

Mar 1, 1906

By G. A. Brooks

Increasing interfacial area through gas injection is one of the main methods for accelerating reaction between slag, metals, and gases in modern pyrometallurgical reactors. In slag-metal reactors, the generation of a large number of metal droplets into the slag phase through high gas velocity has a much larger effect on the overall kinetics compared to the enhanced mass transfer through mixing. Top blowing technology generates large interfacial areas (>300 m2/tonne) through high impingement gas velocity at short distances between the exit of the injection lance and the metal-slag interface. Phase separation may become a limit at the case of very high interfacial areas, though there is still only limited understanding of the trajectories of metal droplets in slag-metal-gas emulsions.

Jan 1, 2003

By S. Kodama, G. Sasaki, K. Matsugi, K. Sugio, Y. B. Choi

"Pure aluminum (Al) matrix composites with changing the volume fraction of TiB2 particle content from 10 to 30% was fabricated by spark plasma sintering (SPS) process. Then the microstructure, density, dispersibility and thermal conductivity of the composites was estimated. As increasing TiB2 content, the dispersibility of particles and the density of the composites degraded slightly. And, the effect of the dispersibility of TiB2 particles on the thermal conductivity was quite little. The thermal conductivity of the composites was less than the theoretical value calculated by Maxwell-Eucken equation considering the effect of the density. It is due the influence of the interface heat transfer rate, because these composites have many small sized particles and have high interface density.INTRODUCTION Recently, metal matrix composites (MMCs) have been used widely in electric / electronic components, architectural materials, transportation equipment, aerospace and a precision instruments, because it’s superior properties have been greatly watched. Demand of MMC for industrial use has been increasing gradually. Furthermore, multifunction properties are required for the composites strongly. By integrating the dissimilar materials, the composites have various properties that we cannot get from monolithic materials. On the other hand, the response to the thermal management is required for materials, recently, and the need for the structural material controlling the thermal conductivity has been increasing. Especially, superior thermal conductivity and good mechanical properties from room temperature to high temperature are required for heat sink and heat exchanger at the same time. In late years, a study on the composites combining carbon materials and aluminum and copper has been developing, and actually the composites with high thermal conductivity which is not provided in the conventional materials is developed. On the other hand, non-oxide ceramics particles such as SiC and AlN, TiB2 have good thermal conductivity. Particularly, as TiB2 has good electrical conductivity, TiB2 containing MMCs is expected as innovative materials used as electric/ electronic components. Furthermore, as TiB2 has low density, high melting point, low thermal expansion and good deformation resistance, the development of high performance composites with multi-functional properties is expected. As thermal conductivity of pure Al and TiB2 are 225 and 66.4 W/mK, respectively, it is expected that the degradation of thermal conductivity by adding dispersant in Al matrix is suppressed. The authors have carried out a thermal conductivity, electrical conductivity, mechanical properties of 20 vol.% TiB2 dispersed Al composites (Sugio, 2016, Sasaki, 2016). In this study, the influence of quantity of addition of TiB2 on microstructure, thermal conductivity was studied minutely."

Jan 1, 2018

By Mathew Cook

Technological developments in Distributed Fiber Optic Sensing and improvements in both hardware and software have allowed fiber optic sensing systems to be deployed in a variety of applications such as pipeline leak detection, perimeter security monitoring, and power cable real time thermal rating. Recently, there has been a larger adoption of monitoring of conveyor belts in so called Conveyor Health Monitiring Systems (CHMS) within the mining and bulk material handling industries to identify idler conditions on an ongoing basis. Several attempts have been made to institute sensing capabilities into conveyors with mixed success. However, recent breakthroughs in modeling, installation methodology, and technology, as well as increased understanding of application and industry requirements, have allowed the technology to be deployed at both experimental and commercial scales. This paper summarizes the application conditions and requirements, design considerations, methodologies used, the outcomes achieved, the logistical and field considerations, and the future possibilities of the use of this technology in CHMS using Distributed Fiber Optic Sensing.

Feb 22, 2026

By Jürgen Schanderl

Cold rolling mills by SMS Siemag are well known for their reliability and long-life cycle. They are an investment in the future. Nowadays mill owners are under considerable competitive pressure and are asked to organize production in a more and more efficient and flexible way. Doing so, a number of elevating screws have to be turned. These are: cutting of operation costs, especially by more efficient equipment and processes as well as transition to more process flexibility to fulfil future product requirements. To support owners in their effort, SMS Siemag offers convincing solutions in cold rolling technology under the brand X-Roll 2.0. Examples to be presented are: Sieflex®-HT drive technology; Redesigned DS system; New reel design: Twin Reel; Emulsion compact unit ECU Compact; TRC® threading assistance system; ECOMode and Energy ADVISOR monitoring system.

Jul 30, 2018

By Rick Piovesan, Pramod Rao, Nihal Bohra, Mark Wahler

"This paper discusses the approach followed for the geotechnical design of 355 mm and 457 mm diameter driven open-ended steel pipe piles used for a gas plant at a green field site in Pilbara region in Australia. The principal bearing layer at the site comprises of calcareous Red Bed soils and weak rock, which is the typical geology along a significant length of the northern Western Australian coastline with carbonate content up to 70%. The uncertainty associated with the mechanical behavior of the calcareous soils and cemented soils (weak rocks) presented design challenges in the selection of appropriate pile design method and design parameters for pile capacity estimation during Front End Engineering Design (FEED). The American Petroleum Institute (API)-based design methodology was adopted. The representative design parameters for the Red Bed weak rock were established by treating the weak rock as clay with undrained shear strength as one-half of the characteristic unconfined compressive strength (UCS) value. Both statically load tested and CAPWAP (Case Pile Analysis Wave Program) estimated ultimate axial pile capacities on 25 early pre-production indicator piles demonstrated that the API design methodology for siliceous soils provides reasonable prediction of axial pile capacity in the red bed soils/weak rock and no reduction to API computed axial capacity due to carbonate content is warranted. The results also demonstrated that penalizing axial pile capacity solely based on carbonate content is not appropriate.IntroductionA gas processing facility was proposed to commercialize the gas reserves located 130 km offshore from the north-west coast of Western Australia (WA). The project site is a green field site located in the Pilbara region along the northwest coast of WA. Specific information regarding the site has been withheld due to confidentiality reasons. The site layout is shown in Figure 1.The site comprises low-lying tidal flats, clay pans and sand dunes covered with low scrub. The onshore site levels vary from elevation 1 m to 10 m AHD (Australian Height Datum), with the largest proportion of the area (excluding sand dunes) between elevations of 1 m and 3 m.The onshore facilities are to comprise a liquefied natural gas (LNG) plant site, a construction camp, the land-based portion of the materials offloading facility (MOF), roadways, and borrow pit areas.The existing ground levels within the process train area, where pile load testing was performed, vary from over 7 m AHD where the summits and peaks of the central dune exist to typically 1 m to 2 m AHD towards the east and west edges of the dune. The proposed finished grade for the process train is set at 7 m AHD."

Jan 1, 2015

By W. C. Whittaker

COMPLETED in November, 1943, at a cost of over $1,500,000, Elk River colliery of the Crow's Nest Pass Coal Company, Limited, has been laid out and equipped for an ultimate annual production of 1,000,000 tons and replaces the recently closed Coal Creek plant, which has been operated by the Company for the past forty-five years. The project has involved the opening of mines in three seams, the construction of a complete set of colliery buildings, including a modern preparation plant of 360 tons per hour capacity, and the laying out of the necessary yard tracks and spur connecting the new development with the Company-owned Morrissey, Fernie and Michel railway, which, in turn, connects with the Canadian Pacific railway at Fernie. The colliery is three and a half miles east of Fernie, B.C., near the southern end of the Crow's Nest coal field, which contains the largest and most important body of coal in the Province of British Columbia. The coal-bearing horizon is the Kootenay formation, present in the form of a syncline covering an area of 230 square miles. Most of the coal seams occur in the lower 2,000 feet of the formation, the covering beds being largely coarse sandstones and conglomerates of great thickness, the presence of which accounts largely for the preservation of the coal measures. James McEvoy, in the report of the Geological Survey of Canada for the year 1900, states that the basin appears to contain a fairly constant coal content of nearly 172 feet in 23 seams of a thickness of one foot or over. Coal has been mined in the Fernie district since 1897 and the first shipments were made from Coal Creek colliery in the following year, over the then newly constructed British Columbia Southern railway. Since that time, a total of over 16,000,000 tons of coal has been produced, an average of 350,000 tons per year. The7ears of peak production were 1910, 1912, and 1913, with an all-time high of 924,000 tons in 1913. The lowest output in the history of Coal Creek was that for the year 1933, when only 60,340 tons were produced, the colliery being closed for some months. Present production from Elk River colliery averages 1,150 tons per day, the output being considerably less than it could be were sufficient man-power available.

Jan 1, 1944

By Nabeel Khan

Annual oil production from the Canadian Oil Sands in Northern Alberta has been rising for several decades, and more ore and overburden are excavated each year from an increasing number of open pit mines. Overburden meeting certain specifications will be used to dam tailings and fill open pits, but the remaining material must be stored in overburden storage structures (OBSS). Well-designed overburden storage structures are more stable and cost less in the short- and long-term. The purpose of this paper is to explore OBSS designs that will be stable yet economical in the short- and long-term. The geological background of the site is briefly discussed, including the effect of each of the main geologic layers (recently deposited till and muskeg, Clearwater Formation clay shales, McMurray Formation oil sands, and the Devonian limestone) on the slope stability of the OBSS. Cost is considered in the analysis when balancing between minimizing costs (steeper slopes) and acceptable factors of safety (flatter slopes), all the while considering the financial consequences of failure. Potential failure planes are identified and probabilistic analysis is conducted on the critical failure surface. The variations in the factor of safety caused by varying pore water pressure, friction angle, and cohesion, are plotted and discussed.

Jun 1, 2012

By D Phillpotts, S M. Mantsho, P Strobos

A challenge on many industrial flotation circuits is controlling concentrate mineral grades using measurements that are provided infrequently. The mineral grades in concentrate streams are a critical performance indicator in any industrial flotation circuit. Failure to achieve concentrate mineral grade targets has significant financial consequences on a flotation operation. A violation of a gangue mineral grade limits by the concentrator may also result in significant penalties. Online grade analysers which can provide reliable real-time grade measurements are essential for effective grade optimisation. The Blue Cube MQi analyser (by Blue Cube Systems) has recently come to prominence for its ability to rapidly determine mineral concentrate grades online and in-stream. This has provided excellent insight into the actual process dynamics in the flotation circuit, and hence enabled real-time control and optimisation of concentrate mineral grades. MintekÆs Measurement and Control division, specialising in advanced control solutions for mineral and metallurgical industries, has had the opportunity to link the FloatStar Grade-Recovery Optimiser to the measurements provided by the Blue Cube system at a nickel concentrator plant. The project initially focused on stabilising the final concentrate grade without directly accounting for nickel recovery. The site later procured additional Blue Cube MQi analysers, resulting in the expansion of the FloatStar Grade-Recovery Optimiser to incorporate recovery component in the performance. This site already had the FloatStar Grade-Recovery Optimiser for several years, but the original grade measurement device was unreliable and ultimately failed. The system was reactivated once the Blue Cube system was installed, replacing the old analyser.CITATION:Mantsho, S M, Phillpotts, D and Strobos, P, 2012. The implementation of FloatStar grade-recovery optimisation control solutions using Blue Cube online grade analysers on industrial flotation circuits, in Proceedings 11th AusIMM Mill OperatorsÆ Conference, pp 363-368 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 29, 2012

By Jasper Kwong

The recycling of MgO-C refractories as a slag conditioner in EAF (electrical arc furnace) foaming slags have been evaluated by the Albany Research Center. The amount of MgO in the slags is critical for the foaming quality. Good foaming slags provide the benefits of high energy efficiency and low refractory consumption and require saturation with MgO. A computer model predicting the chemistry of MgO saturated foaming slags was designed to predict suitable amounts of MgO additives from MgO-C spent refractories. This model can also help to reduce the amount of slags and to improve the economics of producing steel. The implementation of this recycling program is underway at steel plants and the experience of recycling spent refractories will be discussed.

Jan 1, 2002

By H Rossiter, C Simpson, J Market, P Jeanneau

Downhole Assay tools are a geophysical method to collect an instigated response from the material surrounding a drill hole and deliver a multielement proxy-assay. They were first tested in the Pilbara at the turn of this century, however since 2011 they have seen a more focused testing and implementation regime with multiple companies across multiple Pilbara mine sites. The increase in the volume of data has led to advances in the measurements and significant improvements to the efficiency of the calibration process. Pulsed Fast and Thermal Neutron Activation Analysis (PFTNA) downhole assay tools collect gamma photon spectra which are characteristic of elemental signatures. One of the key components of the technique is calibrating the spectral signatures to lab assays. Each tool is slightly different due to the organic nature of the crystal detector and therefore responds slightly differently. Environment and hole conditions as well as ore characteristics are among other external influencing factors. Thus, a unique calibration is required for each tool. In addition, not all elements are measured directly, but some are actually characterised by proxy, meaning that if the signal-to-noise ratio for an element is small, it may be easier to identify the mineral or geology in which that element is found and thus infer the concentration of the element. These proxies may differ for each site or geology type within a site. There is a large advantage to build a unique calibration per tool at each site rather than a universal one to be used across the whole province. This then delivers the accuracy and precision of measurements that mining companies require for modern operations. Early work with the tool required several thousand metres of calibration data and several weeks of analysis to build each calibration. This process has now been streamlined to significantly reduce the amount of data required and the analysis time to make it much easier to introduce new tools to a site with an existing model or to create new models. This paper details the calibration process, illustrating the increasing accuracy of the models as training data are acquired as well as the methods for transferring a calibration from one tool to another.

Nov 8, 2021

By L. B. Rothfeld

In anticipation of RCRA reauthorization and subsequent rulemakings, the Bureau of Mines is studying potential economic impacts of RCRA on mining. For U.S. copper heap and dump leaching operations in a variety of terrains, the cost of liners and closure caps to comply with RCRA Subtitle D ranges from $55 million to $158 million per site, or about $500,000 per hectare ($200,000 per acre). If RCRA technology requirements and financial assurance had been required on current operations, 27 to 100% of production from heap and dump leaching would have been non-competitive at market prices between $2,310 and $1,650 per metric ton ($1.047 and $0.75 per pound) copper. This result is based on an analysis that considers return on capital, corporate overhead, marketing, and freight costs as well as operating and maintenance costs at the mine. Over the same price range, economic analysis using the IMPLAN input-output model on one-or two-county regions indicates potential net job losses of about 570 to 2,700 jobs. Total economic output of those counties could be reduced by about $180 million to $360 million.

Jan 1, 1994

By József Faitli, Barnabás Csoke, Károly Solymár, Zoltán Hatvani, Dimitri Papanastassiou

"Grinding has a significant economic impact on ore dressing/processing, therefore the sizing of mills has an outstanding role.In most cases, the sizing of dry or wet mills for ore processing is primarily based on the determination of the Bond grindability index, using the Bond-Kjos-Rowland relations. In several cases, grinding takes place under conditions different from these and the grinding conditions have a great influence on the post-grinding process. This is particularly true for the grinding of bauxites where grinding takes place in alkali, often in higher temperature (up to 100 ºC) in alkali Liquor. So it is necessary to develop a testing method providing a reliable grindability index even under these special circumstances (grinding in alkalis medium at different temperatures) and allowing a more precise mill sizing. The new heated mill is suitable to determine the grindability index under temperature-controlled circumstances, in liquids with different temperatures (water, alkali). This paper presents in detail the equipment, the conditions (parameters) of the testing process for wet and alkaline grinding, the measuring results and the conclusions."

Jan 1, 2003

By D. Robert Weir, Verner B. Sefton

The reduction roast-ammonium carbonate leach-hydrogen reduction process for laterites has been under development by Sherritt Gordon for the past 20 years. The process can treat high iron or low iron laterites, with some process modification, and gives extractions of 88-93% Ni or 82-88% Ni, respectively. Five campaigns on a 1 tonne per day Pilot Plant and four campaigns on a 35 t/d Demonstration Plant have been carried out on laterite from three different deposits, and many other laterites have been investigated in the laboratory. The Marinduque Surigao Nickel Refinery in the Philippines was designed on the basis of this work. The process comprises roasting to selectively reduce the nickel and cobalt in the laterite, leaching the calcine in ammonium carbonate to dissolve the metals, recovery of cobalt by precipitation of a mixed metal sulphide, concentration of nickel from the carbonate solution by basic nickel carbonate precipitation and recovery of high purity nickel by hydrogen reduction of nickel from ammonium sulphate solution. Ion exchange has been developed as an alternative to BNC and for recovery of trace nickel from BNC barren liquor. Details of the development of some of the process steps through the laboratory to commercial plant are discussed. The process metallurgy has been confirmed in the commercial plant.

Jan 1, 1979

By A. J. S. Spearing, B. Forbes, T. Kostecki, A. Hyett

Improving upon the past understanding of the interaction between installed rock bolts, the immediate roof and sidewalls is vital for the implementation of sound support system design, as this has a direct impact on rock-related safety. This is the primary goal in rock-bolt-related research. The earliest research in this field concentrated on limited laboratory and in situ measurements accompanied by theoretical analyses, based on the Kirsch equations. This represented the initial insight into understanding relative ground movements and their impact on primary support. However, these studies were far from complete. More recently, major technological advances in computing power within the mining industry has changed the scope from theoretical analysis to computer simulation. Even with these advancements our understanding of rock bolts in situ and in the laboratory has not progressed, particularly concerning bending and shear. To measure the behavior of rock bolts, the widely accepted practice is to populate the bolts with an array of strain gauges. Historically, resistive foil strain gauges or long displacement sensors have been used. Additionally, all instrumented rock bolts have used only two diametrically opposed slots. Rock bolts instrumented with these methods have significant shortcomings, one of which is the inability to capture shear and bending. The shearing and bending of rock bolts are particularly common in tabular soft rock mining, such as coal mining. This paper discusses the use of three slotted rock bolts, cut diametrically 120º apart, and two new optical fiber technologies populated along the entire rock-bolt length.

Jan 1, 2015

By F Hungerford, T Ren

"Gas management has always been a major concern for the ventilation officer of any gassy mine. With an increase of mining depth and gas content, there is a great demand for the development of in-seam drilling sites where boreholes can be drilled for the pre-drainage of gas prior to longwall operation. The ventilation and gas management in the drilling site therefore becomes a critical component of mine safety. In this study, advanced computational fluid dynamics technology was adopted to investigate the aerodynamics of gas emitting from the drilling site and boreholes during normal drilling and, in the case of a sudden gas inrush, from the borehole. In addition, the impact of different ventilation controls on gas removal in the drilling site was investigated. Modelling results indicate that gas accumulation zones could be formed if the ventilation system fails to deliver sufficient airflow to the drill site, especially when a sudden gas inrush from a borehole occurs. The configurations of brattice, layout of ventilation tubes and the gas emission rate all have a significant effect on the gas distribution. Due to variations in site-specific conditions, it would be desirable to conduct modelling studies to assess the effects and efficiencies of a ventilation design for the varying environment on-site before carrying out drilling practice. CITATION: Ren, T, Hungerford, F and Wang, Z, 2015. Computational modelling studies of ventilation management for underground in-seam drilling sites, in Proceedings The Australian Mine Ventilation Conference, pp 239–250 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Aug 31, 2015