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By G. R. Harrod

Effective mine operation demands that the right people have the right information at the right time. Caterpillar's Mining and Earthmoving Technology System (METS) meets this demand by providing "real-time" information transfer between the mine offices and machines equipped with the Caterpillar Computer Aided Earthmoving System (CAES). Transfers of mine plans from the mine planning software to CAES-equipped machines give operators access to current mine plans within minutes of their creation. Additionally, office personnel have access to a current digital terrain model (DTM) of the mine site as it is updated in "real-time" by CAES-equipped machines. METS provides mine personnel in operations, planning, and management the information they need when they need it.

Jan 1, 1998

By William G., Pariseau

There are important phenomena in rock and soil mechanics that cannot be explained in terms of theories of homogeneous, isotropic materials. Subsidence of strata about mine openings is an example. In-situ stress measurements in nonisotropic sedimentary, and metamorphic rocks is another. Patterns of joints, faults, fractures, and similar geologic features impart directional mechanical properties to rock masses that are locally isotropic or anisotropic. On the geologic scale, the non-homogeneity of composite rock masses may, in certain instances, be dealt with as homogeneous anisotropy. The mechanics of large rock masses can, therefore, be expected to involve considerations of anisotropy. The source of the anisotropy is not relevant. Once the scale of observation is selected and the material is defined accordingly, the analysis of stress and deformation proceeds without regard to the numerical values of the material constants. There are also important phenomena in rock and soil mechanics that cannot be explained in terms of linear elasticity, theory. For the mechanical description of anisotropic geologic materials capable of de- forming beyond the limit of purely elastic strains, a plasticity theory is required.

Jan 1, 1972

By R Schiller, E Chait

"Quebrada Blanca is a porphyry copper deposit located in the Eocene-Oligocene belt of Chilean Andes. Operation started in 1994 and original reserves for supergene mineralisation gave a life-of-mine (LOM) of 20 years; however, further exploration extended the LOM until 2020.In order to optimise the remaining five years of supergene resource, geometallurgical variables were added to the geological model including copper recovery and acid consumption. LOM plan encompasses finishing the phase number eight and the future development of phases 11 and 13.LOM lithologies include diorites, quartz monzonites, porphyries, igneous and tourmaline breccias. Main alterations are: potassic, phyllic and argillic. Litho-alterations or geometallurgical units were formed by combining five types of rocks with three types of alteration. According to statistical information, the deposit can be represented with 12 litho-alteration units, which cover 98 per cent of the LOM volume.For copper recovery information, there were 40 mini-columns tests made in order to obtain kinetics curves and copper recovery values after comparing the difference between head and tails grades. Acid consumption was obtained using an automatic neutraliser device-based test.Historical data said that copper recovery in pads after 450 days of irrigation is around 75 per cent of recoverable copper while acid consumption is around 5.5 kg/t.According to this study, lower recoveries are related with potassic-altered diorites and argillic-altered quartz monzonites with values around 60 per cent. On the other hand, best recoveries could be found in potassic-altered quartz monzonites and argillic-altered diorites with values closer to 80 per cent.It was also revealed that the most reactive rock is the potassic-altered diorite with 12 kg/t of acid consumption. This rock covers approximately 40 per cent from phases 11 and 13.The final geomet model was calculated using a program that relates each geometallurgical unit with a specific copper recovery and acid consumption value. Results found after comparing model-obtained information with historical leached pads data were used to validate the model.CITATION:Chait, E and Schiller, R, 2016. Adding Copper Recovery and Acid Consumption Variables to the Geological Model of Quebrada Blanca, in Proceedings The Third AusIMM International Geometallurgy Conference (GeoMet) 2016, pp 257–266 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jun 15, 2016

By R. M. Santmyers

The chief compounds of boron are borax and boric acid, both of which have important applications in industry. At present the United States furnishes more than half of the world's requirements of borate materials, practically all from California. Nearly the entire production of borax in this country is under the control of four companies: The American Potash and Chemical Corporation, the Pacific Coast Borax Co., the West End Chemical Co., and the Western Borax Co.

Jan 1, 1931

By K. Unkug

It is commonly accepted that the tension of roof bolts can be used as a measure of the effectiveness of roof support performance in coal bearing strata. The conceptual base for the assumption originates from beam theory. Roof bolt tension acting across the bedding and other weakness planes increases friction, preventing potential separation and slippage within the roof strata and therefore, increases the stiffness of the roof beam between the open face and the rock-mass enclosed within the anchorage. Thus, it is important to monitor roof bolt tension, especially for research purposes, and consequently many measuring systems were developed based on numerous working principles. Research planned by the Department of Mining Engineering at the University of Kentucky required a large number of tension measuring devices of high precision. These were intended to operate reliably in corrosive mine environment over long periods of time. After evaluating the existing systems, it was decided to develop a new type of roof bolt dynamometer which would fulfill the above requirements at minimal Cost. Nearly one hundred such dynamometers were constructed, calibrated and installed in two underground mines. They remained in service for a period of one Year, producing a valuable database for the Project. In this paper the working principle of this new type of dynamometer will be described and technical considerations and samples of the collected data will be given.

Jan 1, 1986

By Sam Warren, Antonio Marinucci, Genesis Z. Figueroa, Anne Lemnitzer

Drilled Displacement Piles (DDP) provide an ideal deep foundation solution that combines the benefits of ground improvement with traditional advantages of piling systems. This paper consolidates data from 20 construction projects in which more than 30 DDPs were installed and tested axially. High quality site exploration data (e.g., Cone Penetration Test and Standard Penetration Test) were evaluated to derive geotechnical analysis parameters. The test sites consisted of mostly mixed soil types with strongly stratified layers of sand, silt, and clay. Pile diameters ranged between 40 cm and 61 cm. Test results were compared with predictive methods developed specifically for DDPs as well as methods used in general geotechnical practice. The accuracy of the empirical methods is presented in terms of total pile capacity, pile length/diameter, and soil type. The large majority of all examined methods underpredict the in-situ pile capacities. It was also found that the difference between the tested and predicted capacity is strongly related to the level of improvement in the surrounding soil due to the piles’ installation. A general comparison between predictive axial accuracy and the observed level of ground improvement upon installation is also discussed.

May 1, 2022

By Christoph Sedivy

Industrie 4.0 is slowly but surely arriving in the melt shops. Furnaces are being equipped with more and more sensors, digital models are increasing the degree of automation, and information is being shared between different aggregates within the plant. Because the electrode control system plays a key role in electric steelmaking, it naturally assumes an important position in the melt shop’s Industrie 4.0 strategy. In addition to reliable, state-of-the-art core regulation functionality, monitoring and reporting tools and the ability to communicate with other equipment are also required. Therefore, the latest generation of our electrode control system, the Melt Expert, was developed based on Industrie 4.0 design principles. Intelligent plant condition diagnostics, performance monitoring, and user-defined reporting are essential modules in this new system. With these functionalities, electrode control systems are developing into the information and control center of the furnace. A newly developed software app brings most relevant process information to mobile devices. This feature allows steelmakers to keep an eye on the performance of their equipment anytime and anywhere. This paper describes the new features of the electrode control system and shares our customers’ operational experience. Our focus is on the practical aspects of plant status monitoring, KPI reporting, and diagnostic functionality as well as the improvements achieved.

Oct 30, 2017

By A. D. Hammond

Until recently, the volumes delivered and unloaded from heap-leaching pads have been estimated by manual methods at Wharf Resources' South Dakota operation. In August 1989, the Engineering Department acquired the MINE-SURVEY software developed by GEM COM Services, Inc. of Vancouver, Canada, as part of a mine planning/grade control software package. The implementation of MINE-SURVEY for pad control resulted in a cost-effective tool to provide accurate and prompt estimates of ore delivered or unloaded from the pads. Volumes can be calculated in a matter of minutes as opposed to hours or days. Another benefit is the ease of comparison of as-build and designed volumes, plotting cross-section in any orientation, importing into AUTOCAD, validation of ore densities and truck factors. This paper describes the application of the MINE-SURVEY systems in heap leaching pad volumetrics.

Jan 1, 1991

By Dao Su, Kelang Mu, Yufeng Guo, Jinghua Zeng, Tao Jiang

"The influence of high pressure roller grinding (HPRG) on sintering of iron concentrate fines was investigated. Results of mini-sintering tests showed that assimilation temperature of iron concentrate fines decreased from 1230 ? to 1220 ? and assimilation time was shortened from 10 min to 5 min when the iron concentrate fines was pretreated by HPRG. Sinter pot tests showed that the yield of sinter increased from 60.33% to 72.92% , tumble index increased from 44.35% to 46.66%. The investigation indicated that, after being pretreated by HPRG, iron concentrate fines are improved in ballability and the fraction of fine particles increased, resulting in the improvement of granulation property and reactiveness in solid state reaction. As a result, sintering of iron concentrate fines were strengthened.IntroductionWith the rapid development of iron and steel industry and the decrease of high-grade ores, the imports of iron ore are increasing continually. It is of immensely strategic importance for development of iron and steel industry and energy security in our country to make good use of iron concentrate fine which is low price, high grade and has a refractory sintering property. When iron concentrate fine is used in sintering, granulation property of sinter mixture and permeability of sinter bed get poor. As a result, yield and quality of sinter fall down. Many researches show that, when HPRG is used in pelletization, quality of pellets is improved dramatically. Meanwhile, HPRG has a low energy consume, a large handing capacity and it is benefit for environment protect. At this theme, strengthening of sintering of iron concentrate fine pretreated by HPRG was investigated in this paper."

Jan 1, 2012

By Charles K. Rose

This paper presents some research studies of the rotary drilling of oil shale at the Bureau of Mines Oil-Shale Mine, Rifle, Colo. The experimental procedures and the rotary drill test equipment are described. Theories of rock drillability, rotary bit cutting action, and bit design are presented and discussed. The actions of various bit designs are analyzed and compared with the observed results of actual drilling tests. A cost estimate is made for drilling Colorado oil shale.

Jan 1, 1955

By William O. Vanderburg

This paper describing the practice at the Wolf Pongee concentrator at Federland, Colo., is one of a series on similar subjects being published by the United States Bureau of Mines. The author acknowledges the assistance of Loach, manager of the Wolf Tongue Mining Co., and of W. G. Roseborough, superintendent of the golf Tongue mill, in the preparation of this paper.

Jan 1, 1933

By C. M. Wai

"Metal species in solid and liquid materials can be extracted by supercritical carbon dioxide containing a suitable ligand. This in situ che1ation-supercritical fluid extraction technique offers several advantages over conventional solvent extraction including minimization of organic liquid waste generation and exposure of personnel to organic vapors. One unique feature of this technique is that metal species can be removed from solid materials directly using supercritical carbon dioxide as a solvent. Several ligand systems including dithiocarbamates, B-diketones, organophosphorus reagents, and macrocyclic compounds have been tested for metal extraction in supercritical carbon dioxide. This novel extraction technique may have important applications for metal recovery and mineral processing.IntroductionSupercritical fluid extraction (SFE) offers several advantages over conventional solvent extraction including the minimization of organic liquid waste generation and exposure of personnel to organic vapors.[1] The high diffusivity, low viscosity, and T-P dependence of solvent strength are some attractive properties which make supercritical fluids excellent candidates for extraction and recovery of organic compounds from solid materials [2] Carbon dioxide is a gas of choice for SFE because of its moderate critical constants (Tc = 31 °·C and Pc = 73 atm), inertness, and availability in purified form. After extraction, the fluid phase is depressurized to separate organic solutes from CO2 gas and the gas can be recycled for repeated use. The SFE technology has been applied to industrial scale operations such as the preparation of decaffeinated coffee and hop extracts."

Jan 1, 1996

By E. L. Rawlins

The development of commercial natural-gas reserves in the Michigan stray sandstone horizon of central Michigan during the past few years has resulted in expansion of the natural-gas industry in that State. The location of the natural- gas reserves of Michigan in the general vicinity of domestic and industrial markets is of economic importance, and in supplying these markets with natural gas a reasonable knowledge of the extent and availability of the reserves is needed in formulating regulations for drilling gas wells and producing natural gas, in analyzing the feasibility of projects to construct natural-gas transmission lines, in promoting and developing markets for the domestic and industrial consumption of natural gas, and In solving many engineering and economic problems common to the natural-gas industry. The development of the natural-gas industry in Michigan has been related closely to the development of oil production. The potential oil production of Michigan is comparable with that in most of the eastern oil-producing States. The development of oil production probably will continue, especially in the central Michigan Basin area; and as wells are drilled to deep horizons in the search for oil, more knowledge will be obtained of the gas reserves in formations above the oil- bearing horizons.

Jan 1, 1936

By J. Kou

The adsorption process, density and structural property of the oleate layer adsorbed onto a hydroxyapatite (HAP) surface at six different concentrations and three pHs (pH 8, 9 and 10) have been studied using the technique of quartz crystal microbalance with dissipation (QCM-D). The present study demonstrated the versatility and accuracy of the QCM-D for surface adsorption characterization. The real-time measurements of frequency and dissipation shifts with a hydroxyapatite-coated sensor revealed changes in the hydroxyapatite surface during the entire adsorption process. Chemisorption and surface precipitation of sodium oleate were also observed on the surface of hydroxyapatite through the use of Fourier Transform infrared spectroscopy(FTIR). Chemisorption dominated at low concentrations and high pH values and formed a rigid and thin adsorption layer. Surface precipitation of calcium oleate and micelles dominated at concentrations higher than critical micelle concentration (CMC) and lower pHs and formed a thick but dissipated adsorption layer with a high hydration level. Three distinct adsorption behaviors were identified from the different slopes of ?D-?f plots. The adsorption density was less than a monolayer at concentrations <0.164 mM, but increased significantly at concentrations higher than 0.821 mM at all three pHs. The critical concentration at pH 8 was 0.33 mM, which was lower than at pH 9 (0.821 mM) and pH 10 (3.3 mM).

Feb 1, 2012

By Dhanvin B. Mehta

Pile testing is generally understood as static load test. It is our common experience that for high capacity, large diameter bored piles, static testing is expensive and time consuming. It is practically impossible to test large number of piles by traditional testing methods. The escalating cost in carrying out a static load test, as well as incomplete information derived therefrom compelled researchers in United States to look for an alternative method of testing for both bored and driven piles. The original research work was carried out at Case Western Reserve University in early 70&apos;s, under the funding of Federal Highway Administration as well as several State Depts. of transportation in United States. The outcome of the research was the development of a state of art field computer for capacity determination, based onOne Dimensional Wave Mechanics.

Jan 1, 1996

By O. C. Blade

The use of Diesel fuel as a source of power is continuing to increase in the United States. The latest available figures indicate that refineries are delivering in excess of 10,000,000 barrels of this type of fuel per month. Factors contributing to this increased consumption are conversions by a number of railroads from steam to Diesel locomotives and the growing use of Diesel engines in buses, trucks, tractors, earth-moving machinery, water craft, and stationary power plants. The increasing importance of Diesel fuel has led to a need for more information on its characteristics, particularly on the grades and qualities currently being marketed. To supply this information the American Petroleum Institute and the Bureau of Mines, United States Department of the Interior, under a cooperative agreement, are conducting annual surveys of Diesel fuels produced in refineries in this country. Samples of Diesel fuel were analyzed by the manufacturers in accordance with instructions from the Motor-Fuels Survey Panel of the Automotive Research Committee of the American Petroleum Institute. Results of the analyses were transmitted to the Bureau of Mines where the data were studied am compiled as shown in the tables of this report. The first survey was made in 1950 and was published as a Bureau of Mines report. The present report shows the results of a similar survey made during 1951.

Jan 1, 1951

Any Australian who knows of the poverty of the early settlers in the first few years following the arrival of Captain Arthur Phillip with his "first fleet" at Botany Bay must feel proud of the progress that has been made in the 174 years that have elapsed since that momentous occasionGFor all its attractive appearance as reported by Captain Cook and Sir Joseph Banks, the shores of Botany Bay and of Port Jackson proved most ,inhospitable, and the accessible country surrounding them anything but suitable for sustaining the life of the small settlement. It is well known that during the first 15 or 20 years the hardy colonists and un-tfortunate convicts were close to starvation on several occasions and were only saved by the arrival of supply ships, which were dependent on the vagaries of wind and current, and the hazards of the uncharted seas they had to -navigate-.When Australia was little more than a miserable penal settlement, Great Britain was one of the great-powers of the world, and the U,.S.A. was an independent nation with a growing degree of prosperity that even then gave promise of its mighty awakening to become, as it has, a e.olossus of industry and commerce,-and the. leader in living standards of the world to-day.Australia, from such a shaky, and comparatively recent start, has risen to a position in which its living standards rank very high in comparison with those of most of the nations of Europe and America. Exact com-parisons are hard to fix because of the wide variety of factors involved .but the Institute of Pab?Lic Affairs .(Victoria) places Australia fifthin the world, excelled only by the U.S.A., Canada, Sweden and Switzerland. The next best after Australia are the United Kingdom, West Germany and France.How we achieved such a high standard of living is a vast subject for study but some of the economic aspects of our climb from abject poverty to a position of near affluence can readily be identified.

Jan 1, 1962

By Terrence R. Lejcher

Strip mining has played a key role in the production of coal used to produce energy in this country. About 56 percent of the 1.3 x 106 hectares (3.2 x 106 acres) that had been disturbed by surface mining as of 1965 can be attributed to stripping (Udall, 1967). The runoff from these stripped areas is usually heavily polluted with high concentrations of total dissolved solids, iron, aluminum, manganese, sulfates, and has low pH values with high acidity. Another problem of a most serious nature in our large cities is the volume of treated solids to be disposed of after sewage treatment. Chicago is presently producing about 664 metric tons/day of dry weight solids (Horn and Earles, 1968). Disposal methods most commonly used include lagooning, incineration, and landfilling. The high cost of land in an urban community is prohibitive of lagoon storage. Incineration and landfill disposal create air and water pollution problems. Many countries including Australia, England and Israel have long realized the value of sewage solids if they are recycled back to the land. In the United States, the value of such solids in reclaiming strip mined land has been recognized by relatively few people. This paper is concerned with the use of anaerobically digested sludge to reclaim strip mined land.

Jan 1, 1972

By Rimas Veitas, James Panton, Erich Steinlechner

"Ductile Iron Piles (DIPs) are a proven, viable alternative to conventional piles, and for the past five years have been successfully used throughout New England. The installation process of DIPs lends itself to both large and small projects. Because of their installation efficiency they provide a substantial cost savings over drilled micro piles. Several New England projects (both end bearing and friction) will be evaluated, focusing on the installation and design procedures.BackgroundThe driven ductile cast iron pile (DIP) is a simple, fast and highly effective pile system. Over the last 30 years over 10 million feet of this pile system has been installed worldwide predominantly in Europe. DIPs are a prefabricated driven pile system utilizing high strength ductile iron pipes which are manufactured using a spun-cast process having outside diameters of 4 5/8” and 6 5/8 inches. The standard pile lengths are 16.4 feet long. The pipes are manufactured with a tapered socket with an internal shoulder for full engagement at the top and a tapered spigot at the bottom. The individual pile sections can be connected with this Plug and Drive® connection to drive a pile of any length.(see figure 1)The DIP system’s inherent advantage is the simplicity of the installation process. The piles are driven to refusal or to a required penetration depth with the use of a high-impact highfrequency hydraulic hammer (ie. Breaker hammer). In most applications the hydraulic hammer is mounted on an appropriately sized excavator (see Photo 2). At the completion of driving the pile, the pile is cut off (see photo 5) and the remaining section of pile is fitted with the appropriate driving shoe and serves as the lead section for the next pile. Being able to reuse the cut off section, yields minimal if any pile shaft waste. The pile is then fitted with an appropriate pile cap plate to receive the load from the superstructure."

Jan 1, 2017

By Ziyad Abunada, David O’Connor, Fei Jin, Abir Al-Tabbaa

"In-situ remediation of contaminated land with deep mixing can enable a multi-technique remedial strategy on the same site combining low permeability barriers, permeable reactive barriers, stabilisation/ solidification treatments as well as ground improvement, delivering significant advantages over alternative strategies. This was the core objective of Project SMiRT (Soil Mix Remediation Technology) which involved the execution of the largest research field trials in the UK to date to provide field validation for this technique. Around 800m3 of soil were treated on a contaminated site in Yorkshire in May 2011 with 6 different treatments, testing ~40 binder compositions and 10 different installation methodologies. Field monitoring, testing and coring activities at the site took place within the first 2 months after treatment and then again at 34 months after treatment. This paper presents an overview of the field activities to date and some 3-year results and assessment of a subset of the treated soil sections. Some good correlations are seen together with some clear differences between treatments. There is generally an observed consistency with depth, with the mixing effectiveness having a more profound effect than the binder composition or content, within the tested materials and ranges. These field trial activities are currently being used in the development of the full-scale commercial remedial strategy for the site.INTRODUCTION AND OVERVIEW OF PROJECT SMiRTWhile there are strong financial and environmental incentives to remediate and redevelop brownfield sites there are also barriers including fear of the unknown, regulatory control, delays, increased costs and the stigma associated with such sites. Hence the remediation process needs to be conducted in such a way to maximise the incentives and overcome the barriers, which is how deep mixing found its niche in the land remediation market. Soil mix technology is such a versatile technique that can perform a number of remediation treatments on the same site. These include low permeability in-ground barriers (cut-off walls), permeable reactive barriers (PRB), stabilisation/solidification (S/S) treatments, other additive related remediation, e.g. in-situ chemical oxidation and bioremediation, as well as soil amendments for greening and also ground improvement all on the same site (Al-Tabbaa et al, 2011). Placed in the context of alternative solutions, soil mix technology could potentially replace the five techniques shown in Figure 1, which would be required to deliver the same treatments mentioned above. Treatment trains strategy, where a combination of techniques in succession are used to both reduce the contamination levels and deal with residual contamination, is becoming common in land remediation and the use of one set of equipment to deliver this would bring about significant financial advantages. In addition, soil mix technology has many other advantages in terms of speed of implementation, elimination of exposure to contamination, elimination of off-site disposal and low cost. Soil mix technology for the remediation of contaminated land emerged in the UK in the mid 1980s and has since been employed in over 30 or so projects, which far exceeds its application to ground improvement for which only a handful of jobs have been carried out to date."

Jan 1, 2015