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By C. Newman, N. Schaefer

"INTRODUCTION As underground mining continues to operate at deeper depths and in more complex geologic and geometric conditions, there has been an increased demand for higher design standards in ground control safety and stability within the mining industry. Over the past 20 years, NIOSH has developed, validated, and distributed a number of free software packages (ALPS, ARMPS, AMSS, ARBS, etc.) for the safe design of underground coal mines with respect to ground control. While these programs were initially developed on a, “stand alone model,” where all program data resides on an individual or workgroup computer, modern day web applications have begun to migrate toward a, “multiple-tier model,” allowing multiple users to access an application through an Internet connection. webGroundControl provides users with access to NIOSH ground control design software (ARBS, ALPS, and ARMPS) utilizing a web-based three-tier architecture allowing users to easily access ground control designs, perform on-demand calculations, and provide online collaboration between operational personnel and engineers through a web server. Given advancements in cloud computing as well as the expansion of Internet connectivity on the surface and underground, webGroundControl users will be able to access the applications anywhere (where permissible) at any time. As web-based computing technologies continue to advance and cloud computing gains popularity and momentum, there is an industry need to develop Internet based applications for mine and ground control design (Barczak et al., 2016). The purpose of this paper is to introduce and familiarize those in the mining industry with the basic framework and, more specifically, the user-interface of the webGroundControl application. It is expected that the mining industry will rapidly embrace this new product and webGroundControl will be a new paradigm for mining engineering computer applications. APPLICATION ARCHITECTURE With the advent of cloud computing, web-based applications have become more popular with their adoption of multiple-tier, or n-tier, architecture containing independently operating tiers. The three-tier application architecture utilized in webGroundControl (as outlined in Agioutantis and Newman, 2016) contains a Presentation Tier (Web Server), Logic Tier (Logic/Application Server), and Data Tier (Data Server) as shown in Figure 1. While tiers have the ability to be deployed across and operating on multiple servers, webGroundControl is currently being deployed on a single server located on a university desktop computer. The separation of the application into a series of tiers greatly increases the maintainability and scalability allowing for the adoption of new technologies that can be applied to a single tier without redesigning the software package. The Presentation Tier maintains the user interface translating client requests (through a web server) and displaying results (through a web browser). The Presentation Tier allows for on-demand access from multiple users and compatibility with a variety of personal computers, Smartphones, tablets, etc. on different operating systems. The Presentation Tier has been developed with respect to the HTML and JavaScript languages. Through the utilization of CSS, a coding language which describes the style of an HTML document, the webGroundControl display is able to spontaneously adapt to any browser and any screen. The development of the Presentation Tier will be discussed in more detail in subsequent sections of this paper."

Jan 1, 2017

By Ning Wang, Tengfei Guo, Wanyan Li, Hanjie Wen, Hannian Gu, Zehai Li

Red mud has been reported as a potential resource for lithium. To investigate the leaching behavior of lithium, a lithium-rich red mud was neutralized with hydrochloric or oxalic acid and then leached with acetic acid. When red mud was neutralized using dilute hydrochloric acid, about 58 to 60 percent of lithium was leached with 25 percent acetic acid at 95 °C for 60 min, while more than 95 percent of sodium and 85 percent of calcium were dissolved in the leachate solution. When oxalic acid was used to neutralize red mud prior to acetic acid leaching, lower lithium leaching efficiencies of about 42 to 47 percent were observed. Nevertheless, these leaching efficiencies of lithium were close to that of calcium and much higher than those of sodium under the same conditions. In this study, 25 percent (v/v) of acetic acid at 85 °C for 60 min was demonstrated to be the optimum conditions for lithium extraction from oxalic acid-neutralized red mud using acetic acid. The results are useful and of interest for lithium recovery and purification from red mud.

By Michael Gay, W. H. Hansmire, G. Rippentrop, V. S. Romero

The new Tren Urbano heavy rail transit project in San Juan, Puerto Rico has one very significant part, the Río Piedras Contract, being constructed underground. This paper will give an overview of the tunneling work that started construction in1997. Design-Build procurement for tunneling is addressed. The new and modern transit system in San Juan will be 17.2 km (10.7 mi)long and have 16 stations in its first segment of construction, which is due to open in 2001. The line connects the city center district of Santurce to the outlying suburban municipality of Bayamón. All construction is being done under design-build contracts as a demonstration project funded by the Commonwealth of Puerto Rico and the Federal Transit Administration (FTA). The Río Piedras Contract is completely underground and involves practically all types of construction in soft ground. One station is built as cut-and-cover at the University of Puerto Rico. One portion has twin tunnels to be driven with an Earth Pressure Balance Machine (EPBM) and lined with one-pass precast concrete segments. Another has four short tunnel drives at a turnout that will be constructed with an initial support of shotcrete and lattice girders (i.e., the New Austrian Tunneling Method of construction). The most complex construction is the Río Piedras Station, which is being built as a stacked drift with a total of 15 individual tunnel drifts. After being sequentially excavated and concreted, they will form the arch of the 19 m (62 ft.) wide by 16 m (53 ft.) high cavern station. This structure is excavated in soil with less than 5 m (16 ft.) of cover to overlying historic buildings.

Jan 1, 1999

By Eugene W. Price

One of the most important fundamental characteristics of iron ore pellets is their porosity. This importance arises from the fact that the pores are the busy avenues whereby many changes are brought about in the life and form of the pellet from the time it is made until the iron it contains emerges as a molten stream from the blast furnace. As a green iron ore pellet is first heated in the drying cycle of a typical heat-hardening process, the pores act as conduits to allow the escape of steam from the water or vapor from the oil which served as binders to hold the green pellet together. After the release of the steam (or oil vapor) the pores then act as conduits whereby oxygen can enter the pellets to 1) convert magnetite (Fe304) to hematite (Fe203), if appropriate, and 2) promote solid state grain growth between adjacent particles of iron ore. The rate of oxidation and the rate of grain growth are directly related to pore size' and pore size distribution. Rate of oxidation is also directly influenced by length of pore and length of pore is obviously related to pellet diameter. It is well to keep in mind that the heat-hardening process does not harden the mineral grains themselves. What it does is weld them together to change the green pellet from a doughy mass, composed of thousands of tiny individual particles, into a strong, intergrown monolithic structure. In the blast furnace the pores again act as conduits for gases, but in this case they trans¬port reductants such as hydrogen (H2) and carbon monoxide (C0) which remove most of the oxygen from the ore. Rate of reduction is also directly related to pore size and pore size distribution.

Jan 1, 1967

"A commercially available through-the-earth (TTE) communications system was evaluated at an underground coal mine in eastern Kentucky. This field study was conducted as part of a larger multisite evaluation of available TTE systems. The mine detailed in this paper was idled at the time of the study, which provided the nearest practical representation of a postevent mine shutdown environment. For this study, surface-to-underground and undergroundto- surface communications were tested. Standard deployments of the TTE system using the manufacturer’s recommended procedures were able to achieve clear communications between underground and surface locations. Other arrangements of the units yielded mixed results. Future experimentation is planned to further examine the phenomena observed at this mine IntroductionThe ability to establish effective communication between surface and underground personnel after a mine event is essential for both evacuation and rescue efforts. Current wireless underground communication technologies are reliant on intermediary physical infrastructure, such as antennas and repeaters, to enable underground communications. As such, communications are easily disabled during a mine event because of the inherent vulnerabilities to physical damage (Damiano, 2012; National Academy of Engineers, 1970; Yenchek et al., 2011). A true emergency communications system would function regardless of a mine’s physical state. Through-the-earth (TTE) wireless communication technology only requires the use of a single transmitter and a single receiver to achieve point-to-point communication through solid strata. With this capability, TTE systems have the potential to serve as a true emergency communications platform."

Apr 1, 2016

By J. D. Miller, C. L. Lin, J. Dong

Nano clay mineral particles such as kaolinite — with primary particles typically smaller than 2 μm in size — can cause significant problems in flotation processes and tailings disposal, including the processing of Florida phosphate rock and Canadian oil sands. In this study, the consolidated state of flocculated kaolinite sediment was examined, and high-resolution X-ray microtomography (HRXMT) was applied to describe the structure of the consolidated sediment. Using this tomographic information, the complex geometry of the channel network structure for the consolidated flocs was established for the first time. With the establishment of the experimental channel network structure, permeabilities were estimated by flow simulation using the Lattice Boltzmann method. Results for kaolinite sediment with and without polymer are compared and discussed. Results for flocculated kaolinite sediment in a gravitational field are also presented and discussed. The results show that as polymer dosage increases, the permeability of flocculated kaolinite sediment increases, and as suspension pH increases, the permeability of flocculated kaolinite sediment decreases.

By Robert L. Marovelli

Organizational development that attempts to simultaneously deal both with training and with job design parameters as they relate to mine health and safety, productivity, and quality of life is one of several areas of research that the Bureau of Mines is pursuing. The Bureau sees potential in this particular effort for reducing accidents and injuries, improving worker satisfaction and health, and increasing productivity.

Jan 1, 1981

By Joel L. Morrison

Wet bituminous coal fines from active and abandoned slurry impoundments are currently being examined as a recoverable feedstock for the production of coal water slurry fuel (CWSF). Preliminary analysis indicates that these coal fines can be converted into low solids, low viscosity CWSF with acceptable stability without the use of viscosity modifiers (dispersants) or stabilizers. Efforts are now underway to determine if the impounded coal fines can be economically cleaned by froth flotation to an ash level of < 12 wt. % and a total sulfur content of 1.2 wt. %.

Jan 1, 1995

By A. A. El-Midany, R. M. Farag, A. M. Salem, S. E. El-Mofty

Bentonite is one of the main players in the stability of drilling mud. Its particle size and particle size distribution significantly affect drilling mud’s rheological properties. Although the Specifications for Drilling Fluids Materials report on Oil Companies Material Association (OCMA)-grade bentonite states that the API recommended powder having 2.5 percent mass fraction as the maximum value of residue of diameter greater than 75 μm, there is no other information on the specific size distribution for API bentonite. It was found that API bentonite has a specific size distribution with specific mixing weights. It is important to investigate why that mixture represents the optimum properties of drilling mud and how each individual size fraction has a specific function in the mixture. To clarify the effect of individual size as well as the collective effect of the size distribution, API bentonite was classified into different size fractions, with each tested separately for controlling properties such as filtration loss, plastic viscosity, gel strength, cake thickness and packing density.

By L. L. Oriard

There are certain site-specific geological and physical features of a rock mass which control its behavior under the dynamic stresses induced by the action of explosives. It is essential that blasting technology be adapted specifically to those features. There does not exist a single, simple "right" way for each type of blasting operation, but rather each operation must be custom-designed for each site. When this is done, it is often possible to produce unusual but highly desirable end resglts, such as undisturbed narrow rock walls, monoliths and square benches. Although the techniques illustrated here were developed specifically for "sculpture blasting", the geomechanics principles would apply to other types of blasting control, both large-scale and small-scale. Because the techniques are designed more for the purpose of modifying the site responses which would ordinarily be expected than they are to developing new "blasting formulae?, the name "Modified Site Response Blasting" will be used.

Jan 1, 1984

By V. V. Ershov

Mining geometrical graphic documentation is employed on a large scale in designing and planning of mining operations at all the stages of exploitation. Mining geometrical modelling of mineral grade distribution presents an independent type of mathematical (graphic) modelling. The idea of functional relationship between geological indices being observed, and spicier coordinates is the basis of traditional mining geometrical modelling. Graphic presentation of three independent variables P =f (x,y,z) is confined to obtaining the series of two independent variables functions. Independent variables are presented as topographic surfaces corresponding to plane cross-sections of a deposit. During exploitation of certain parts of a deposit the most reliable geological information is obtained, characterizing regularities of ore distribution in the entrails. This information is, though, not taken into account in goemetrization of the new areas. In this connection dynamic modelling of deposits in the process of exploitation is necessary, i.e. geometrization of the deposits should be dynamic.

Jan 1, 1986

By Z. J. Hladysz

The Hladysz Rock Tester was developed at the South Dakota School of Mines as a portable rock strength tester. The hand held device is placed against a rock surface and struck by a hammer. The impacted force causes a steel ball in the device nose piece to indent the rock and simultaneously indent a standard steel bar also contained in the nose piece. By comparing the two indented diameters the compressive strength of the rock can be calculated using laboratory determined correlation coefficients.

Jan 1, 1984

By John P. Anderle

A tectonically disturbed sequence of Mississippian age evaporites expressing a 5 milligal negative gravity anomaly near Sussex in southeastern New Brunswick, Canada, was investigated by a program of drilling, geologic and geophysical work over the past 27 months. Seventeen of twenty-one drill holes have penetrated 10 to 140 feet of potash mineralization in a salt sequence underlying 2 000 to 3 000 feet of arenaceous, conformable red beds, also of Mississippian age. Bromine and borate studies, lithological characteristics and geophysics, have facilitated improved understanding of the salt structure. The salt sequence has been affected by f1owage which has resulted in both major and minor folding. In the more disturbed areas, the potash interval was extensively subterraneally eroded at the upper anhydrite-salt contact.

Jan 1, 1978

By Bob Katsiouleris

Having passed through the worst of times for industrial minerals demand, there are signs that the best of times lie ahead. If the downturn was the result of unsustainable economic policy, the path forward has everything to do with sustain-ably meeting the demands of more people enjoying higher standards of living than ever before. Minerals producers must be poised to understand and meet their requirements well into the next decade. Successfully marketing industrial minerals - the building blocks of a growing and increasingly urban world population - will depend on producers? ability to respond nimbly to a rapidly changing and regionally evolving macroeconomic environment. A renewed focus on energy conservation, sustainable agriculture and building practices and consumer demand for products with a smaller environmental footprint will drive product and market segmentation strategies. These trends will not only shape the way industrial minerals producers do business, but also the type of skills and people they will require to run those businesses.

Jan 1, 2011

By R. Patterson

Tracer gas sampling methods are useful for monitoring ventilation systems, especially in remote or inaccessible areas, and can be utilized for analysis of the ventilation system immediately following a mine emergency. However, the success of this technique is largely dependent on the accuracy of release and sampling methods. Analysis of sampling methods is crucial for rapid response and dependable results during emergencies. For the purpose of this study, four well-accepted sampling techniques currently used in the mining industry were compared using solid-phase microextraction (SPMe) fibers with sulfur hexafluoride (SF6), an industry standard, as the tracer gas. Current sample collection techniques include plastic syringes, glass syringes, Tedlar bags and vacutainers. SPMe fibers are used in a variety of industries, from forensics to environmental sampling, and are a solventless method of sampling analytes. To analyze these sampling methods, samples were taken from a 0.01 % standard mixture of SF6 and nitrogen and analyzed using electron capture gas chromatography. A relative standard error of less than 10% validated results to compare the accuracy of various methods. The technical and practical issues surrounding each sampling method were also observed and discussed.

Jan 1, 2011

By P. Davis

With new mineral deposits found in areas of difficult terrain, and annual production capacity increasing in mines over the last decade, the aerial ropeway is proving to be a viable, economic method of transportation from mine to processing plant. Of the more conventional designs, a bicable ropeway is more suited to difficult country than the simpler monocable. The bicable, however, does have limitations in the difference in levels it can accommodate in one section at a given capacity. This is noticeable where hilly terrain and high capacity imposes a limit on the length of each section. Increasing the number of sections for a relatively short conveying distance tends, in the case of conventional bicable, to unbalance the normally favorable economics of the ropeway. In addition to analyzing hauling rope stresses, other areas have to be considered when looking at high capacity ropeways. Bucket capacity, speed, and the wheel load on track ropes are examples. These and other factors led British Ropeway Engineering Co., of Sevenoaks, Kent, UK, to produce the twin-track system. Using twin track ropes, larger capacity buckets, and, if the height differential warrants, the installation of twin hauling ropes, BRECO produced a ropeway design for areas of hilly terrain and at higher capacities than had been considered suitable for aerial ropeways. Designs have been produced for systems handling 1.5 kt/h (1,650 stph), and the potential exists for expansion to above 2 kt/h (2,200 stph). The arrangement of ropes provides high stability of the cars and is especially suited to areas where high winds occur during normal operation. This development allows the aerial ropeway to be applied economically in difficult areas and at the increasingly high capacities demanded by engineers. Ropeway Transports Limestone to Sudan Cement Plant Maspio Cement Corp. of Atbara, Sudan, will soon use an aerial ropeway to deliver its entire limestone requirement 20 km (12 miles) from quarry to plant. The Atbara plant is located north of Khartoum, near the east bank of the Nile River. The quarry is west of the river, in hills rising from flat desert country. The original transport system was a 24-km (15-mile) railway from the quarry to the west bank and a monocable ropeway that crossed the Nile and continued to the fac¬tory, a distance of about 2.5 km (1.5 miles). This original ropeway had a capacity of 60 t/h (66 stph). With the extension of cement-making capacity in the late 1970s, 2.5 kt/d (2,755 stpd) of limestone was required and a new mono-

Jan 3, 1984

By N. Careddu

In recent years, slabs with a rough surface have captured a large share of the ornamental stone market. However, the main technologies used for this type of treatment are based on mechanical shock (bush-hammering) or thermal treatment (flaming or flame-finishing). These traditional technologies are widely used, but have many limitations that decrease their usefulness. The purpose of this study was to develop a technology that enhances the natural colors of the rock and produces a rough surface without compromising its mechanical characteristics, in contrast to traditional technologies. This report shows the technical, economic and aesthetic results obtained with a new water-jet treatment and compares it with competing technologies.

Jul 1, 2010

By W. L. O?Connell

[Patent Issue No. Date Issued To Subject 386,504 July 24, G. Sweanor The separation of quartz from a 1588 metal with a liquid such as CS2 or CHC13 under water by introducing mixture into water layer. Quartz will stay in water layer while metal sinks through organic.]

Jan 1, 1963

By Thomas R. Mills

Under contract to the U. S. -Department of.-Interior, Office of Coal. Research, Hittman Associates recently completed a 16 month study of the environmental-factors associated with the siting, construction, and operation of large scale coal refineries. (1 2) The objective of this study was to identify the environmental effects and to define the magnitude of these effects and the approaches which can be used to mitigate adverse environmental consequences. In the study, the five major coal bearing regions of the country having reserves adequate to support a number of large scale coal refineries were considered. The regions considered were: Appalachian, Eastern Interior, Fort Union, Powder River, and Four Corners.

Jan 1, 1975

By Spencer R. Titley

Porphyry copper deposits in the southwestern Pacific area represent relative newcomers to the growing number of occurrences of this mineral deposit type. In addition to firmly establishing the importance of this region and its potential influence within the framework of world copper resources, the deposits of this region are significant from a scientific point of view because of their close relationship to the phenomena of Island Arc evolution. Since the discovery of Panguna on Bougainville in 1964, the list of prospects, proven and unproven, and developments, has grown to more than twenty and the number continues to increase. At the time of this writing, the number of prospects is imperfectly known but the following localities and numbers are fair minimum approximations: Manus (Admiralty Islands) (3); New Britain (5); New Ireland (1); Guadalcanal (2); New Guinea Highlands (6); Misima (1); and Fiji (2); Proven prospects are present in the new Guinea Highlands (2); one deposit is being developed in Test Irian, and one orebody, on Bougainville, is in production. This summary paper concerns a discussion of some of the geological characteristics of producers, developments, and prospects on the Islands of Nets Guinea, New Britain, Bougainville, Guadalcanal, and Manus. I am not aware of publishable data for Misima or Fiji. As so many variables ultimately determine whether or not a porphyry copper occurrence becomes an orebody, not the least of which is geography, this summary treats the characteristics of these occurrences which alloy; their assignment to the porphyry copper category. For purposes of this discussion, I have considered those copper occurrences which are apparently genetically related to talc-alkaline intrusions and in which the content of copper has been upgraded 50 to 100 times the Clarke for that particular host rock. Some of these occurrences are shown on Figure 1.

Jan 1, 1973