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"The Mine Haul Road Optimization Alliance is an Australian industry-academia collaboration which has been developed to support mine haul road operators by fully integrating mine road design research solutions with industry end-user service providers to design, assess, implement and monitor the various equipment, materials and road management strategies required to optimize the safety, environmental and economic performance of a haul road. Initially, a broad overview of the university-industry collaborative landscape is presented, following which the current situation in the Australian mining sector is reviewed both nationally, and on a country-wide basis, internationally. This insight places realization of a collaboration between Curtin University Western Australian School of Mines Mining Engineering and Metallurgical Engineering (WASM ME2) and the Haul Road Optimization Alliance (HROA) industry members into context of opportunity. Following an overview of the HROA collaborative structure, aims and objectives, it is shown how academia and industry can collaborate to deliver a more robust solution to mine haul road design, performance or management needs, especially where integrated solutions are needed. Critically in this approach, implementation and monitoring data provided by industry and service-providers alike forms the foundation on which to develop research knowledge and innovation that is more responsive to the end-user requirements, typically represented by ‘early goals’ and implementable solutions. The paper concludes with examples of how the alliance collaborations work in practice to deliver improved mine haul road designs and optimized operational performance, together with the mechanisms used to ensure industry needs are met through focused, end-user driven research and integrated solutions implementation."

Jan 1, 2016

By H. D. Dahl

In January, 1969, the Central Research Division of Continental Oil Company initiated a research program on roof control. The purpose of the research was to improve roof stability. Toward this end, it was necessary to determine which of the many geological and geometrical variables have a significant effect on roof stability. The isolation of these significant variables would allow research effort to be concentrated where it would be most effective in improving roof control. The research effort was directed toward two major objectives. One was to de-fine the geological and/or geometrical parameters that affect the severity of roof conditions in any particular area of the mine. This study was concerned with roof fall intensity. The second was to define why roof falls in Humphrey No. mine (and in northern West Virginia-south-western Pennsylvania coal mining areas) are oriented so that they occur primarily in north-south rooms or entries. This study was concerned with roof fall orientation. To provide a reference framework for further discussion, a geological description of the area is presented in Part II. In Parts III and IV, the procedures, methods, and 'results of the research applied toward the afore-mentioned major objectives are presented. Part V contains the conclusions and recommendations for-warded by this study.

Jan 1, 1971

The mineral sands industry is oriented primarily toward the supply of titanium (Ti) raw materials (titanium feedstocks) for the production of titanium dioxide (TiO2) pigment and titanium metal. Titanium minerals ilmenite, rutile and leucoxene, and titanium slag and synthetic rutile are all used principally as feedstocks for the production of white TiO2 pigment. It accounts for almost 90 percent of the world?s consumption of titanium minerals. The remainder is used for the production of titanium metal, fluxes for welding rods and as a metallurgical flux in iron and steel making. Titanium dioxide pigment is produced by two alternative process routes, the sulfate process or chloride process. The bulk of the world?s titanium dioxide is derived from the mineral ilmenite, which also contains iron oxide and other minor impurities. At some mining operations, the iron present in ilmenite is removed (ilmenite beneficiation) to produce a high TiO2 feedstock (slag or synthetic rutile) typically containing between 80 percent and 95 percent TiO2. Pigment producers then further process it to produce pigment.

Jan 1, 2011

By S. Lu

The particle-bubble attachment and the rupture of formed aggregates in flotation cell were investigated in terms of turbulent regime. It was found that the particle-bubble collision rate is closely correlated to the energy barrier between particles and bubbles, and no adhesion takes place for the hydrophilic particle-bubble system due to the introduced ?capture efficiency? f(a) being zero. The values of an especially defined Weber number, i.e. the ratios of turbulent stress to aggregate strength in the inertial subrange of turbulence were estimated, the results showed that the detachment of a particle from a bubble involved in an aggregate is mainly caused by the turbulent stress only in the impeller zone, no bubble splitting occurs both in the impeller zone and in the bulk zone.

Jan 1, 1993

By Thomas P. Meloy

Theoretical development of comminution models has come about in the last 10 years. These models assume that the material being broken is homogeneous and that the compression or energy wave is uniform throughout the specimen. Obviously, this is not the case because most comminuted materials are rocks with either many phases and/or definite grain size. The mathematical models deriving the size distribution of daughter fragments resulting from the comminution of brittle, single particles are of two schools. The first model, proposed by Gilvarry in 1961, was based on the concept of volume, surface, and edge flaw activation. The second, proposed by Meloy in 1960, was based on the concept that the crack density is a function of the energy in the comminution wave. The flaw theory has run into increasing theoretical problems and is now being abandoned. On the other hand, the crack density theory has been expanded and has successfully considered the case where there are inhomogeneities in the comminutive wave. However, the main constraint of a homogeneity in the solid being comminuted has hitherto never been overcome. In this paper, a very general derivation of the crack density model is made for inhomogeneous solids by replacing the assumption of homogeneity with an arbitrary function, P(y), which describes the susceptibility of the material to comminution as a function of position. The restraints on this function, P(y), are very broad and, hence, the derivation is extremely general. General use of the equation derived necessitates a detailed a priori knowledge of both the fracture process and of the physical properties of the material being fractured; this knowledge is expressed in open form as, P(y), the linear probability density that a plane of fracture intersects at point y on an arbitrarily oriented line segment of total length xo through the original particle. From these assumptions, a general expression for the cumulative mass distribution of particles resulting from fracture is then postulated. It is: [ ] where, B(x), is a cumulative mass of material finer than size x, r is the average number of crack,, (y), is defined above and xo is the initial particle size. It is shown that suitable assumptions reduce the expression to the theoretical results of Gaudin and Meloy and to special forms of the empirical equations of Rosin-Rammler, Gaudin and Schuhmann. Semi quantitative agreement is demonstrated by Grimshaw with experimental results of a very complex fracture of heterogeneous sandstone blocks. A need is expressed for more theoretical development of P(y), and a more extensive experimental study of both homogeneous and heterogeneous fracture. The full mathematical derivation is presented for the first time in this paper. The general implications of the equation and its application are also discussed.

Jan 1, 1968

By A. Podlesny, E. N. Rubinstein, J. J. Sammarco, B. Demich

Roof bolting typically follows the extraction of a commodity to help keep the roof from collapsing. During 2004 to 2013, roof bolter operators had the highest number of machinery-related injuries, accounting for 64.7 percent, at underground coal mines. This paper analyzes U.S. roof bolter fatal and nonfatal lost-time injury data at underground work locations for all commodities from 2004 through 2013 and determines risk indices for six roof bolting tasks. For fatal and nonfatal incidences combined, the roof bolting tasks in order of the highest to lowest risk index were bolting, handling of materials, setting the temporary roof support (TRS), drilling, tramming, and traversing. For fatalities, the roof bolting tasks in order of the highest to lowest risk index were handling of materials, setting the TRS, bolting, drilling, traversing, and tramming. Age was found to be a significant factor. Severity of injury, indicated by days lost, was found to increase with increasing age as well as with increasing experience, largely due to the confounding of age and experience. The operation of the roof bolting machine used in underground mining should be a research priority given the high frequency and severity of incidents. The results also suggest that temporal factors may exist, so additional research is warranted to better understand these factors and potentially develop interventions. This research provides a datadriven foundation from which future research can be conducted for safety interventions to reduce the frequency and severity of incidences involving the roof bolter activities of bolting, handling of materials, and setting the TRS.

Jan 1, 2016

By W. Roggenthen, Z. J. Hladysz, G. D. Callahan, W. G. Pariseau, W. Weinig, C. Randolph-Loar, R. Popielak

A Deep Underground Science and Engineering Laboratory (DUSEL) is being planned at the site of the former Homestake Gold Mine in Lead, SD, under the sponsorship of the U.S. National Science Foundation (NSF) in cooperation with the Department of Energy (DOE). This national facility will host a variety of multidisciplinary science and engineering experiments, including physics experiments that require shielding from cosmogenic radiation. Current plans include construction of large rooms (up to 55 m in width) at depths of 1.48 km (4,850 ft) and 2.25 km (7,400 ft) below the surface. Preparation of the preliminary design required the development of a geotechnical characterization program, including preliminary drilling and coring, core logging, drill hole mapping with a televiewer, drift mapping of the geology and rock structure, in situ stress measurements, and laboratory testing of the mechanical properties of the rocks and discontinuities. Overall rock quality is very good to excellent. Site investigations included geotechnical assessments for the construction of caverns and laboratory modules. The results are favorable and reaffirm selection of the Homestake site for establishment of a Deep Underground Engineering and Science Laboratory.

Jan 1, 2011

By Claude M. Moreland

It is common practice when thermally drying coal from wet coal preparation facilities that the coarse +0.5mm fractions and fine fractions (-0.5mm) are combined and fed to a thermal dryer. There are very good reasons for this concept. The coal feed is much easier to handle in this condition for it is not as likely to stick inside the dryer or hang up in the material handling equipment, and is easier to feed and discharge. However, it is generally only the -0.5mm fines that really need to be dried. The +9.5m fraction of the cleaned coal will leave the dewatering screens, or drain and rinse screens, at an acceptable surface moisture, probably 5 or 5 ½ percent. The 9.5m x 0.5mm mesh fraction can be centrifuged to about 8 percent. The -0.5m fines can range from 18 to 22 percent or more, depending upon the type of equipment employed to dewater, and upon the size distribution within this size range.

Jan 1, 1982

By James Giulianelli

Personnel at the Jet Propulsion Laboratory (JPL) are studying the technology and applications of salt-gradient solar ponds (see below) for both electrical and thermal energy generation. The brine extraction and processing site operated by the Kerr-McGee Corporation at Searles Lake, California, offers ideal conditions for economic construction of solar ponds. Furthermore, since rising conventional energy costs adversely affect the economic recovery of brine by the present process, this site was selected for a study on the feasibility of integrating the solution mining of trona (Na2CO3?NaHCO3?2H20) in the lower salt with solar ponds for heating. The major emphasis of this study was to determine whether inexpensive thermal energy available at the brine extraction site would be useful in extracting increased mineral value from the resource. The present operation, which involves the simple extraction of the complex brine and its processing at the adjacent plant, is sometimes referred to as solution mining. Since the concept discussed in this paper involves injecting a heated sodium sulfate brine to dissolve carbonate underground, the proposed scheme is referred to as "enhanced" solution mining. The subject is discussed in greater detail in a recent JPL report. (1)

Jan 1, 1981

By F. H. Seymour

Central to Newmont Gold's Mine planning system is the ability to interactively perform cut and fill operations on topographic contours and to accurately evaluate grades and tonnages within contour outlines using polygon set manipulation routines. This paper develops the applied geometry concepts that underlie these routines. Included are representation of volumes with contours, point in polygon test, block proportion in polygon calculation, polygon area and centroid calculation, and intersection, union, and complement between polygon sets.

Jan 1, 1990

By T. Naarttijärvi

The Fabian ore body near Malmberget, Sweden, has an ore reserve of 5 Mt of predominately low grade iron ore, containing 40-55% Fe. Mining began in 1971 with a new method called slot block caving. About 2 Mt were mined, but poor fragmentation resulted in too much secondary blasting. This decreased mucking efficiency to such an extent that the method was abandoned after only 40% of the ore volume had been mined. At this stage a large stope (180 x 30 x 100 m) had been excavated. Although the exposed area was quite large, no caving action occurred in the hanging wall or in the ceiling. LKAB decided in 1977 to introduce sublevel stoping using 105-mm-diam holes. This was the first time large diameter holes were used underground in Sweden. The method had been evaluated in collaboration with the University of Luleå (LuH), the Swedish Detonic Research Foundation (SveDeFo), and the Swedish Mining Research Foundation.

Jan 3, 1982

By AKIHIRO YOSHIMURA, HIDEKAZU KATO, KOTA TAKATORI, YASUNARI MATSUNO

Chalcopyrite (CuFeS2) is the most refractory copper mineral when treated in conventional sulfate media leaching systems. This is the first study to examine the use of a dimethyl sulfoxide (CH3SOCH3, DMSO) solution containing copper chloride (CuCl2) for the leaching of chalcopyrite. Leaching experiments for a copper concentrate composed mainly of chalcopyrite were conducted at ambient pressure at 313–413 K. The leaching fractions of Cu, Fe, S, Au, and As were investigated. It was found that 90% of the Cu was extracted in 2 h, and 94% was extracted in 4 h at 373 K, which is competitive with other conventional processes. A DMSO solution containing CuCl2 could selectively dissolve the valuable metals Cu and Au from chalcopyrite, but leave minerals with little economic value such as pyrite (FeS2) and As in the residue. Chalcopyrite is oxidized by cupric ion in proportion to the stoichiometric ratio of Cu in the concentrate to the initial cupric ion in the DMSO solution, which is enhanced by the presence of oxygen below 373 K.

Mar 12, 2021

By D. K. DeForest

The olfactory system (sense of smell) is crucial to the ability of fish to avoid predators, recognize kin, and synchronize reproduction (Baldwin et al. 2003). Copper (Cu) has been shown to impair olfaction in juvenile freshwater life stages of salmonids (including Pacific salmon and trout) in some laboratory experiments; and in the United States, public concerns have been expressed that current regulatory criteria for Cu in fresh water are not adequately protective of olfactory function in salmonids (e.g., OSU 2007; Pearson 2007). These concerns have largely been raised because some Cu concentrations that have caused olfactory impairment in salmonids in the laboratory are less than Cu concentrations that have been shown to reduce salmonid survival, growth, or reproduction (the effects endpoints that are typically considered in deriving ambient water quality criteria). However, two important and interrelated points that must be considered: (1) freshwater Cu criteria are "driven" by the sensitivities of several invertebrate species that are more sensitive than the olfactory impairment threshold in salmonids when (2) the influence of water chemistry on Cu bioavailability is properly considered in deriving Cu criteria. Bioavailability refers to the ability of various chemical forms of Cu to interact with receptors on the surface(s) of organisms and thus directly cause toxicity or uptake by the organisms. The toxicity of Cu and other metals to aquatic organisms is a function of water chemistry. For example, acute Cu toxicity in fresh water generally decreases as pH, water hardness (Ca2+ and Mg2+), alkalinity, and dissolved organic carbon (DOC) concentrations increase (Meyer et al. 2007). The U.S. Environmental Protection Agency (USEPA) has recommended hardness-based freshwater aquatic life criteria for Cu and other metals since the 1980s (e.g., USEPA 1985); and hardness-based metals criteria decrease (i.e., become more restrictive) as water hardness decreases. More recently, the USEPA has recommended freshwater aquatic life criteria for Cu based on the biotic ligand model (BLM; USEPA 2007), which accounts for the influence of multiple water chemistry parameters, including DOC, pH, alkalinity, Ca2+, Mg2+, and several other cations and anions. The BLM-based Cu criteria generally decrease as DOC concentration, pH, alkalinity, and water hardness decrease. Because DOC has a stronger influence on Cu bioavailability than water hardness, hardness-based and BLM-based Cu criteria can differ considerably. For example, in water that has low DOC and high hardness, the hardness-based Cu criterion would be relatively high (because it is driven by the high hardness) but the BLM-based Cu criterion would be relatively low (because it is driven by the low DOC). Thus, any evaluation of the protectiveness of Cu criteria against a given effect, such as olfactory impairment, must properly account for the chemistry of the exposure water. Meyer et al. (2013) compiled data on Cu-induced olfactory impairment and olfactory-induced behavioral effects from tests in which BLM parameters were measured. They demonstrated that the USEPA's BLM-based freshwater life criteria for Cu are protective against olfactory impairment, because it adequately accounts for water chemistry (whereas the USEPA's hardness-based Cu criteria are not consistently protective). Olfactory impairment by Cu is now receiving increased attention in Canada and Europe (e.g., Wall 2013; Stang 2013). Accordingly, in this paper we have expanded the analysis of Meyer et al. (2013) to consider copper guidelines from various other countries and whether these guidelines are protective against olfactory impairment.

Feb 23, 2014

By D. P. Bryan

An aggregate resource study was done for southern Washoe County, Nevada, which contains the Reno-Sparks metropolitan area and a population of about 300,000. The study included an inventory of existing operations, projection of future demand, identification of potential aggregate resources based on geology, and determination of economic potential of these resources. Economic potential was determined by the integration of GIS layers that included aggregate potential, distance from market, distance from major and minor transportation arteries, and elevation. The investigation resulted in a determination that resources of high quality aggregate sufficient for future consumption are present in southern Washoe county; the limiting factor for future utilization is accessibility.

Jan 1, 1996

By Duane L. Abata

This paper discusses recent technology dealing with the use of computer graphics in the mining industry and presents a newly developed computer software package specifically designed for use in underground mining operations. This software package, developed under a United States Bureau of Mines contract, 1) displays mine ventilation schematics and other representative illustrations for a real time data acquisition system and 2) utilizes the Bureau-owned Minefire and Ventilation Code for display of ventilation and contamination predictions on the microprocessor system. The package utilizes a unique system of display indexing that provides a simple yet efficient method of recalling a series of mine schematics detailing an underground operation and an alarm acknowledgement scheme that provides an effective method of identifying problem areas which may exist in the mine network. The package was written in Fortran for a 64 kilobyte, Z80-based microprocessor-computer.

Jan 1, 1984

By W. A. Hoyer

Neutron activation analysis for mineral identification has attracted the attention of numerous investigators, judging from the publications on this subject in the past few years. 1-9 The appealing aspect of this method of mineral analysis is its proven sensitivity in the laboratory. In principle, activation analysis is one of the few petro-physical methods whereby a direct analysis for a mineral itself is possible in a borehole. The successful application of activation analysis requires the use of particular neutron reactions, measurement of selected gamma-ray energy intervals, and optimum bombardment and detection times. For copper analysis, Labanov et al., 10,11 using a low-energy PuBe source, reported an acceptable logging means. On the other hand, Pradzynski12, in analyzing ores and process tailings, used high-energy neutrons and photons for surface measurements of process samples. The work of Labanov et al. was based on measuring the rate of decay of the activated copper and hence was not as definitive as might be desired. Equipment is commercially available to carry out activation studies in the field 13,14 Gamma-ray spectra can be successfully transmitted over ordinary logging cables and, with borehole high-energy neutron accelerators and lower-energy chemical neutron sources, a variety of neutron activation methods can be studied. The purpose of the study discussed in this paper was to determine the feasibility and practicability of logging for copper using neutron activation techniques and commercially available equipment. The laboratory study showed that Cu could be detected in rock samples in the laboratory by high-energy neutron activation of 63 Cu. In the field, however, due in part to the large volume irradiated, the direct detection of copper using high-energy neutrons was not as promising. Detection of copper by measuring both the direct gamma-ray emission and the excessively strong low-energy gamma-ray absorption appears promising. Copper was not detected either in the laboratory or

Jan 1, 1972

By Immo H. Redeker

The Kings Mountain area of North Carolina is the lithium pegmatite center of the U.S., if not of the whole world. We have two spodumene and by-product mineral producing companies, Lithium Corp. of America, and Foote Mineral Company. We also have Kings Mountain Mica and Kings Mountain Silica Companies producing mica. feldspar, quartz and clay from weathered pegmatites in that area. Figure 1 gives the location of the spodumene pegmatite area in North Carolina. The two spodumene producers mine typical pegmatite ore in open pits after removing amphibolite or mica schist overburden which is sold to aggregate producers. The ore reserves are discussed elsewhere in this session. They are in the order of plus 50 million tons but not unlimited. 1.2 The major minerals found and concentrated from the North Carolina spodumene pegmatite ores are tabulated on Table 1.

Jan 1, 1977

By K. Heatwole, D. Shier, A. Davis, J. Kidder, S. Sunkavalli

"Acid rock drainage (ARD) is produced when sulfides are exposed to oxygen and water. Oxidation reactions typically result in a depression of pH and leaching of solutes and metals. Many oxidation models have been developed based on oxygen diffusion, but in environments with high permeability, other transport processes (i.e., convection and advection) can play an important role. Multiple sulfide mineral phases with differing oxidation rates should also be incorporated. WROC, a finite-difference model, was developed to account for these factors in predicting ARD. The program includes sulfide mineral oxidation using a shrinking core mechanism, heat transfer by conduction, heat of reaction and oxygen transport by diffusion and advection. The model was validated using data from the literature. After validation, the WROC model was used to simulate several different waste rock scenarios, including different forms of sulfide mineralization and the effect of implementing a waste rock cover. The results demonstrate that including specific sulfide mineral phases can have a significant effect on oxidation and that implementation of a cover can also aid in reducing waste rock oxidation.IntroductionAcid rock drainage (ARD) is a notable environmental concern in areas where rock or other material with acid generation potential is disturbed. ARD is defined as drainage that occurs as a result of sulfide oxidation in rock exposed to air and water. ARD is characterized by low pH, elevated metals concentration (especially aluminum, iron and manganese), sulfate and high total dissolved solids. The low-pH water that results from acid generation is capable of solubilizing heavy metals contained within the rock. The principal sulfide mineral in mine wastes is pyrite (FeS2). Pyrite oxidation is complex and can involve chemical and biological reactions. Oxidation of pyrite by atmospheric oxygen produces one mole of Fe2+, two moles of SO4 2- and two moles of H+ for every mole of pyrite oxidized, as described by Eq. (1)."

Jan 1, 2015

By S. S. Pathak, S. Mishra, M. H. Tyeb, A. K. Majumder

Roping in hydrocyclones is a well-known phenomenon in mining and mineral industries which put serious restrictions on their continuous and maintenance free operation. Roping is mostly observed in association with high underflow solid concentrations which can be attributed to higher fraction of solids reporting to the underflow or the feed solid concentration itself being higher. This paper proposes a newly designed spigot with a truncated conical geometry which can allow for a rope-free discharge at higher feed solid concentrations. The experimental observations revealed that in the operation of a 50.8-mm-diameter hydrocyclone, roping ensued at 10% to 12.5% (wt%) feed solid concentration depending on feed inlet pressure for the cylindrical spigot, whereas with the modified spigot, rope free discharge was attained even at 25% (wt%) feed solid concentration.

Jan 8, 2022

By Paul Wellman

The energy problem of the U. S; was emphasized by the oil embargo of late 1973 and early 1974 and it seemed for a time that the Federal Government, under pressure from the general public, might take some corrective action. However, this was not the case. With the gasoline lines gone and an apparent plentiful supply of petroleum products, public concern quickly dissipated., This country is more vulnerable to an oil embargo today than we were in 1973-1974 and this fact should be of concern to all our people. Since 1968, we have used oil and natural gas at a much more rapid rate than we have been able to find new domestic sources; thus, there is an increasing gap between domestic production and consumption and we have filled the gap with ever increasing oil' imports. These imports have increased at an alarming rate in the recent past, some 58 percent in 1976 compared with 1975. Imports are nearing 8 million barrels per day. Then, by applying some simple arithmetic, at $12 per barrel, the resulting trade deficit is $96 million per day or $35 billion per year. Obviously, this cannot be tolerated by our economy over a long period of time. Historically, we have shifted from one fuel to another as is shown in this slide. In 1850 about 90 percent of our fuel requirements came from direct combustion of wood, by 1900 we shifted to coal for 70 percent of our fuel, and now about 78 percent of fuel requirements comes from oil and natural gas. The difference is that the previous shifts were voluntary and the one facing us now is of necessity.

Jan 1, 1977