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By D. G. Ball

Other than being used to convey fill material for the gob stowage or building of ribside packs on advancing longwell faces, pneumatic conveying has not been used for the transport of materials on a large scale in mining operations. The technique is extensively used in the wood products industry for conveying wood chips, limestone and other ingredients for the manufacture of paper, for the transfer from railcars, barges or ships to silos or stockpiles and further transfer into the pulp mills. This method of material transfer has the distinct advantage of transporting suitable material over horizontal and vertical distances within the same system. In considering material associated with mining, this includes, ore, coal and rock up to 4 inch cubed size, throughputs of 200 tons per hour over horizontal distances of 3000 feet or vertical lifts of 2000 feet. In recent years tests have been carried out to determine the physical and economic limitations of pneumatic hoisting, the results of which have led to the installation of two fully productive coal hoisting systems at mines of the National Coal Board in Great Britain. The equipment used for the pneumatic hoisting of coal or waste rock is described in this paper, together with a brief history of the tests which led up to the installation of the two hoisting systems in Great Britain.

Jan 1, 1977

By W. A. Weimer

Coal and coal mining is no longer the mighty king of industry and in our daily lives and homes that it once had the privilege of commanding. Many of you will remember that one of the chores of your youth was to bring in the scuttles of coal, morning and night, to feed the heater or stoke the furnace in the morning and bank it at bedtime. Growth of gas and oil have displaced coal in home furnaces and commercial buildings, and have taken over some segments of industrial markets. The coal burning locomotives have virtually disappeared in favor of the more efficient diesel engine. However, coal as a prime mover still holds its strategic position as is evidenced by act that the electric power industry almost entirely depends upon coal for its generation.

Jan 1, 1961

By Patrick R. Taylor

Iron phosphate glasses are promising host matrices for vitrifying actinide rich nuclear wastes materials because of their high solubility of actinide oxides, high chemical durability, and relatively low melting temperatures. An iron phosphate waste form was developed at the University of Missouri-Rolla. The structure and property of the waste form were well characterized by materials techniques. However, to scale the process and advance it to commercial viability, it is necessary to understand the processing parameters, such as the partitioning of waste elements and the viscosity as a function of temperature. Viscosity of 40 Fe203 - 60 P205 mole % iron phosphate melts (prepared with phosphorous pentoxide and ferric oxide) at 1000-1200 C was measured by the rotating-spindle method. It was discovered that this fluid has non-Newtonian behavior. Experiments were performed to study flow properties following the Standard Test methods for Rheological Properties of Non-Newtonian Materials by Rotational (Brookfield) Viscometer (ASTM D 2196-86). Samples prepared using ammonium phosphate and ferric oxide showed Newtonian behavior and the temperature dependence of the viscosity was studied over the range of 1000 to 1200 degrees C. The difference in flow behavior between the two fluids was analyzed in terms of preparation conditions and variation in the final composition and phases. The partitioning behavior of waste elements in the iron phosphate glass was studied by melting in a high temperature furnace and JCP analysis. The experimental results show that the solubility of Ce and Sr in phosphate glasses is significantly higher than the solubility associated with borosilicate glasses. This strengthens the conclusion that iron phosphate may be a viable alternative to borosilicate glass for immobilization of high heavy-metal-content wastes and actinide rich wastes.

Jan 1, 2002

MR. J. F. MYERS, Consulting J3eneficiation Engineer, Greenwich, Conn.: In the written discussion contributed by Mr. F. C. Bond in item ( 2) (page 515), speaiking about the significance of the ratio of mill diameter to the make-up ball diameter, he states: "When this ratio exceeds 100 the power and capacity of the mill are de-creased"; and the paragraph ends with a reference to the 30 per cent ball volume "with some de-crease in mill capacity". I believe this broad statement is incorrect. When we are dealing with a non-cataracting mill, pre-ceded by a good rod mill, there is a slight increase in capacity, but the power does drop. The second point that I consider needs consideration is Mr. Bond's item (8), Proper Mill Speed (page 516). This paragraph should be qualified to cover single-stage mills only. It does not apply where a rod mill is followed by a non-cataracting ball mill. The statement as is, with no qualification, gives an erroneous idea of proper mill speeds.

Jan 1, 1957

By J Cronin, R Burgess-Limerick, T Horberry, L Steiner

"Automation offers the mining industry great potential for improvements in productivity and safety. However, the experience of introducing automation in other industries has been that the full potential of new technology is not always realised. Designers are surprised, for example, to find that automation does not eliminate human errors. Unwanted and unexpected consequences also arise if the introduction of automation fails to consider how people will adapt to the new technology. A focus on the technical aspects of automation is necessary but not sufficient for success. The potential for improvements in productivity and safety promised by automation will only be achieved if the joint cognitive system that emerges from the combination of humans and automation is designed to perform the functions required for system success. This case study describes the human factors issues associated with the introduction of automation generally, and describes a case study of the successful implementation of loader automation at Northparkes mine.Information obtained through a site visit and interviews with operators, safety staff and the project manager revealed the following strategies for successful design and implementation of the automation system: involve the people who will be impacted encourage constant communication between operators and designers provide operators with essential information avoid providing non-essential information provide the operators with flexibility empower operators to take action take advantage of the new possibilities automation provides.CITATION:Burgess-Limerick, R, Horberry, T, Steiner, L and Cronin, J, 2017. Mining automation human-systems integration – CMOC-Northparkes case study, in Proceedings 13th AusIMM Underground Operators’ Conference 2017, pp 93–98 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 16, 2017

By David Lowell

"The paper point out the cycles of metal prices, and cycles of exploration that tend to lag one year behind metal prices. It appears that mergers and acquisitions are likely to continue in the currentvolatile industry environment, and a two-tier industry will evolve with giantcompanies representing the upper tier and juniors the lower. Strategic alliances will become more common, but irregular and inefficient exploration financing will continue unless the majors make a specific and consistent effort to solve this problem, and also show more discipline in balancing metal prices and production levels. "

Apr 24, 2001

By Raymond B. Ladoo

"The name bentonite has been applied to a group or series of clay-like materials characterized by an alkaline oxide and alkaline earth content of 5 to 10 per cent, fine grain Giza, high absorptive powers, and usually very strong colloidal properties.Bentonite probably represents no mineral of fixed composition, and its physical properties vary considerably. The type material from Wyoming is light yellow or greenish yellow in color, but from other localities it may be cream colored, white, gray, pink, dark brown or even black. It is exceedingly fine grained, very plastic and highly absorbent. The appearance may be dull or powdeay, but a freshly cut surface usually has a waxy luster. Some varieties have the appearance of wax and may be cut into very thin, translucent shavings. The fracture of the type material is roughly conchoidal, that of other varieties is platey and shale-like, while still others have no typical fracture. Bentonite is highly absorbent; .hen wetted it will absorb more than three times its weight or seven times its volume of water. Some varieties when wetted with water expand to more than six times (some experimenters report eight times) their original volume. The wetted material is exceedingly smooth and soft and feels like soft soap. Unlike most clays, bentonite is easily fusible at a comparatively low temperature.Under a high-power microscope bentonite seems to consist of extremely small, more or less rounded, grains of uniform size, but the texture of most varieties is so fine that individual grains can not be distinguished.Some varieties when finely ground and thoroughly agitated with water will stay in suspension indefinitely, forming a translucent gelatinous mass. The addition of small amounts of acids or sodium chloride seems to have little or no tendency to raid coagulation or settling. Other varieties of similar analysis and appearance go into suspension more easily, but settle out again in a comparatively short time. It has been suggested that the material which stays in suspension indefinitely is a true colloid of the emulsion or lyophilic type."

Oct 1, 1921

By P. Gao, J. W. Yu

"Magnetizing roasting-magnetic separation is an important route for the beneficiation of refractory iron ores. In this investigation, a pilot-scale fluidized magnetizing roasting reactor was introduced and used to study the effects of roasting temperature and the flow rates of reducing gas CO and fluidizing gas N2, on the magnetizing roasting performance of an Anshan-type carbonate-bearing fine iron ore. The results showed that the hematite was almost reduced to magnetite by a gas mixture of 4 m3/h CO and 1 m3/h N2 at a roasting temperature of 540 °C. Under the optimized conditions, a high-grade magnetic concentrate assaying 66.1 wt.% Fe with a recovery rate of 91.2% was achieved from an Anshan-type carbonate-bearing fine iron ore assaying 42.0 wt.% Fe. The XRD, VSM, and optical microscopy analyses revealed that the siderite was successfully converted to magnetite by roasting. Some coarse hematite particles were difficult to reduce to magnetite completely; however, these generated magnetite particles with a fine hematite core could also be effectively recovered by magnetic separation after liberation from gangue minerals due to their strong magnetism. INTRODUCTION Magnetizing roasting followed by low-intensity magnetic separation has been considered as an effective solution, both technologically and economically, when upgrading refractory iron ores (Zhang et al., 2012; Peng et al., 2012; Li and Zhu, 2012). According to the type of roasting reactor, the magnetization roasting can be divided into shaft furnace roasting, rotary kiln roasting, and fluidized bed roasting (Zhu and Li, 2014).Shaft furnace magnetization roasting system is mainly composed of heating and reduction processes. The hematite ore is first heated to 700~800 °C in the heating zone, then falls into reduction zone where the weakly magnetic hematite is reduced to magnetite by coke oven gas at 550~600 °C (Yan et al., 2012). However, several years of engineering practices indicate that the shaft furnace can only process the hematite ores with a granularity of 15 ~75 mm, and the shaft furnace roasting is also characterized by heterogeneity of roasted product. Hence, the shaft furnace magnetization roasting technology is gradually replaced by high-gradient magnetic separation with the development of high-gradient magnetic separator. The rotary kiln generally handles the hematite ores with a grain size of less than 30 mm (Zhu and Li, 2014), however the formation of clinker ring in the rotary kiln will affect the yield of iron resource. In the fluidized bed furnace, the hematite ore is shaken up by an upward current of gas which maintains the individual particles in suspension (Yu et al., 2018). The precise adjustment of the gas velocity to the particle size and the specific weight of the hematite ore, make it possible to generate a floating mixture of gas and solids which behaves almost like a liquid (Yu et al., 2017a). The process is reported to have the following advantages over the other roasting techniques: ease of control due to absence of moving parts within the reactor, homogeneity of roasted products, ability to handle fine particles, and high efficiency of heat transfer and mass transfer (Li et al., 2015; Yu et al., 2017b). However, the simultaneous heating and reductive magnetization of hematite ore occur at the same place in the conventional fluidized bed reactor. Therefore, the reductive atmosphere, as well as the safety and stability of anti-explosion are hard to be controlled. Besides, the roasting temperature for conventional fluidized bed furnace is usually up to 950~1150 °C (Liu et al., 2017). Thus, the formation of clinker ring caused by high temperature will affect the operating efficiency."

Jan 1, 2018

Leaving the relatively simple life on a uni student and venturing off in to the outside working world is a big step. There are two paths to follow, the æContikiÆ style graduate program where you pick up your new lease vehicle and set forth on two to three years of planned activities, or can pack everything into one bag, stick a copy of æthe rough guideÆ in your pocket, and set off on your own graduate adventure. I took the path less travelled.The less followed method of developing yourself isnÆt for everybody. Parts of the journey are difficult and sometimes it feels hopeless, but itÆs all a learning experience. Along the way you might not get to all the graduate ætourist stopsÆ like dragline, truck-shovel, or drill and blast. But youÆll see most of them and pick up a lot more of the local culture such as people management, operational knowledge, quality control, and the black arts of project financial management.

Jan 1, 2004

By T. D. Moore

Methane emission from two surface gob-degasification boreholes was measured by the Bureau of Mines. The investigation took place during mining of a 3,200-foot longwall panel in the Lower Kittanning coalbed in central Pennsylvania. The first hole was 500 feet from the start of mining, and the second hole was 2,200 feet. The first hole went on natural draft as soon as the longwall face passed it. This caused the methane flow in the return entries to drop 75 pct. In the 6 months required to complete the panel, the two holes emitted 69 MMcf of methane in varying percentages of concentration in air. In 3 years, the holes emitted a total of 150 MMcf of methane.

Jan 1, 1976

By J. M. Demarthe

The recovery of minor metals from zinc concentrates is dependent on the process used for their treatment. The behaviour of gennanium and indium in pyrometallurgical processes such as the Imperial Smelting furnace or the cupola furnace is of practical importance. The .Anaconda process for the treatment of zinc leach residues is not well suited to the recovery of valuable minor metals, and new technologies must be studied. In this regard, a solvent extraction process, using Kelex 100, developed by Minenet Recherche for the recovery of gennanium from dilute sulphate leach solutions is described. Also, new hydranetallurgical techniques in chloride media can be applied to the purification and concentration of minor metals depending on the stability of their chloro-complexes and the valency of associated inpurities. A synthesis of methods is proposed to address the problems related to the recovery of valuable minor metals in the zinc industry.

Jan 1, 1990

By Robert D. McKellar, Luke Frawley, Richard Okrasa

"The resource industries in Canada are facing increasing global competition and stringent environmental regulations. This has made it essential for companies to lower operating costs wherever possible. Electrical energy rep-resents one variable cost that may be better managed and utilized, providing the user with lower operating costs, improved productivity and better yields.The utility industry is also facing changes in the way it must do business. Utilities in North America are facing the prospect of deregulation that will eliminate the monopoly they have traditionally held. This will force them to strive for lower operating costs, to maintain a competitive position and to improve customer ser-vice so as to maintain their customer base.Ontario Hydro has been working with industry for several years. Many opportunities for cost savings have been identified involving energy efficiency, process improvements and the use of new electro technologies. One useful service that the utility can offer industry is to increase the awareness of potential opportunities suited to their operations. This paper will provide an overview of some of the projects that have been implemented and those that are presently being evaluated. An electronic data-base of electro technology applications that is under development will also be described."

Jan 1, 1996

By M Scoble, E Rubio

The re-engineering of manufacturing production systems has demonstrated the benefits from using production information for optimising processes. This paper explores the techniques and issues in the acquisition and analysis of mine production data for tactical decision making in production control. The use of information and operations management tools is presented in the context of block caving studies, with particular focus on the relationship between secondary breaking and LHD production performance.

Jan 1, 2000

By Robert Peretti, Antonio Zucca, Andrea Manni, Silvia Serranti, Paolo Massacci, Marcello Ghiani

"This research study aims to identify the best way of processing colemanite concentrates, which is sometimes characterised by a high content of As sulphides, finely disseminated in the matrix of the boron mineral.Scanning Electron Microscopy analyses have been carried out to identify all the mineralogical constituents and to evaluate their distribution, frequency and mutual relationships.Colemanite concentrates are mainly used by chemical plants producing boric acid and gypsum. A high As content is unacceptable for further use of tailings coming from the leaching process and is very dangerous if the tailings are released into the environment.Grinding tests were conducted under dry and wet conditions in order to assess how As sulphide minerals are released from colemanite minerals.Some of the difficulties involved in obtaining selective liberation of As sulphides from colemanite minerals were overcome, although a certain decrease in As grade in the higher size classes was registered.All comminution products have been analysed by SEM, monitoring the degree of liberation of the mineralogical constituents.Flotation tests have been carried out, following different comminution flow sheets and adopting different modulating conditions in order to evaluate the influence of the following parameters:- collector concentration versus contaminants concentration (As minerals) in the froths;- kind and quantity of the frothing agent to maximise mineral recovery in the froths;- kind and quantity of the modulating agents to maximise the selectivity of the process;- conditioning modalities in order to obtain a suitable dispersion of fines and avoid segregation of Asbearing particles together with colemanite ones;- solid/liquid ratio of the pulp to minimise the water flow into the plant.Information obtained from SEM analysis has been adopted to evaluate segregation phenomena in pulp and in flotation products."

Jan 1, 2003

By T. L. Tanton

Introduction Sturgeon River area, on the east side of lake Nipigon, Ontario, was the scene of a gold rush in 1934. According to press reports, the active staking during the latter part of the summer spread out rapidly from the early holdings until it embraced practically all of the lower basin of Sturgeon river in a belt up to ten miles wide extending west from Kinghorn for 35 miles to lake Nipigon. And, before winter set in, active prospecting and claim staking reached beyond lake Nipigon to areas where belts of ancient schists were known, notably west of Obonga lake. The writer's familiarity in past years with the areas to which attention has been directed admits of some observations on means of access in the field, the general geology, and the progress that has been made in identifying formations favourable for the occurrence of gold. Canoe Routes From the writer's observations in Sturgeon River area in 1917 and in the Obonga Lake area in 1933, it is recalled that there is, locally, a striking dif~ ference in the accessibility of the two areas by travel along canoe routes. Sturgeon River area is easily accessible from Kinghorn or Jellicoe stations on the Canadian National railways. Many small lakes, commonly of the linear type and with elongations east and west, occur among the forested rocky ridges near Jellicoe (Figure 1) and to the east and west along, or adjacent to, Sturgeon river. This stream has long stretches with gentle current between the falls and rapids. The drainage system provides excellent canoe routes (Figure 2), and the interruptions to travel (Figure 3) are remembered .as scenic features that were passed by portages with firm footing. West of Obonga lake, the streams flowing easterly to lake Nipigon may be followed through scenic canyons to a plateau of law relief characterized by extensive muskegs and shallow, brown-water lakes; and along small streams, where beaver dams have been destroyed, there are muck ponds where the usual alternatives of paddling or portaging can be dismissed in favour of the 'moosing' method of progress with the canoe (Figure 4).

Jan 1, 1935

By E. Swartzman

"DURING 1951, experimental cleaning studies on both fines and larger sizes of certain Canadian coals were conducted on a relatively large scale in two pilot plants in the United States, large enough to be considered as small commercial units, and in one commercial plant in Canada.One of the pilot plants was a wet washer of a type which apparently has never been .used in Canada, nor has any Canadian coal been tested in it before. In the other pilot plant and in the commercial plant, dry cleaning equipment was used. The commercial plant is the first of its kind to be employed in Canada, and this type is used only to a limited extent in the United States.Fine-Coal Cleaning ExperimentsTest PlantsHydrotator and Hydrotator-Classifier combination pilot-plant with a capacity of about twenty tons per hour. This is a classifier type washer adapted for cleaning fine coal as well as certain intermediate sizes. The Hydrotator deals with that portion of a coal retained on approximately a 24-mesh Tyler sieve, whereas the Hydrotator-Classifier deals with the minus 24-mesh fines."

Jan 1, 1952

By X. Cao, H. Huang, Z. Dai

"Crystal phase of copper-containing slag regulation by the slag viscosity, cooling speed and cooling method, where the slag viscosity is related to the temperature and alkalinity. According to the mineralogy properties of a copper-containing slag, experiments of crystal phase regulation and flotation were conducted. When the copper-containing slag that adding a small amount of calcium oxide was cooled slowly at a rate of 3°C/min and about 1050°C n a cinder inclusion system, the viscosity of slag can be remained under 0.25 Pa·S and more than ??% of copper particles that the grain size is larger than 20 ?m in slag. The whole flow of flotation experiment was carried out to recover copper from the copper-containing slag with crystal phase regulating and the copper concentrate grade was ?????%, the recovery efficiency of copper was 94.18%.INTRODUCTIONChina's annual output of copper slag is more than 6 million tons, the current total has reached 80 million tons. It is equivalent to 640 thousand tons of copper metal with the copper grade of 0.82%. Most of the smelting slag were storage. It is not only occupy the land and pollute the environment, but also make a huge waste of resource (Alp, Deveci, & Süngün, 2008; Carranza, Iglesias, Mazuelos, Romero, & Forcat, 2009; Gorai, & Jana, 2003), therefore, it is good way to achieve copper slag resources by the effective recovery of valuable component from copper smelting slag, which is an important measure of the current process of copper smelting slag and implement the central authorities to vigorously develop the circular economy, improve the recycling of resources, increase copper production of intensive development (Zhou, et al., 1994; Zhang, Zhang, & Wang, 2005). Currently, researches on comprehensive utilization of the coppercontaining slag made a much progress (Wei, 2004; Liu, Gai, Yang, Sui, Li, & Fu, 2008; Liu & Zhu, 2008; Zhang, 2010; Sun, Chen, & Tang, 2012; Qin, Wang, Ren, Wei, Peng, & Gu, 2012). Flotation is one of the most effective method to recover the copper from smelting slag, which has the features of low cost and high efficiency (Song & Liu, 2001; Zhang, Wang, & Li, 2012). But the copper particles in the copper smelting slag distribution is very uneven, and the thickness of the material is very serious. The copper content in the micro level is higher, the size of copper sulfide ore is less than 0.043 mm, which leads to the difficulty of the monomer dissociation (Tossavainen, Engstrom, Yang, Menad, Lidstrom, Larsson, & Bjorkman, 2007; Moustakas, Mavropoulos, Katsou, Haralambous, & Loizidou, 2012). In this study, according the process mineralogy of a smelting copper slag, the crystal of smelting copper slag was optimized by controlling the temperature, alkalinity, cooling rate and cooling method, which makes the fine copper mineral particles in the copper slag crystal further, and can be used to meet the particle size requirements of flotation, thereby enhancing the flotation of copper."

Jan 1, 2016

By John J. Mazza

Treatability studies were performed to determine the effectiveness of two commercially available treatment methods (solvent extraction and thermal desorption) for the removal of PCBs and PAHs from contaminated dredged riverbed sediments. The solvent extraction method evaluated was the B.E.S.T. process which extracts the contaminants with triethylamine. The thermal desorption method utilized was the ATP process which desorbs the contaminants at elevated temperature in an anaerobic atmosphere. A description of both methods and. an evaluation of the treatability study results is provided. Each treatment method was used to treat two separate samples (high and low concentration) from the site. Overall, both methods proved to be very effective with solvent extraction achieving 98% removal of both PCBs and PAHs and thermal desorption achieving better than 99% removal of both the PCBs and PAHs from the high concentration sample. Both solvent extraction and thermal desorption achieved greater than 99% removals of PCBs and PAHs from the low concentration sample. Vendor cost estimates for full scale treatment were roughly equivalent. The primary differences between the two methods lies in the realm of permitting, operational requirements, and emission concerns.

Jan 1, 1994

By S. Aktas

The present work describes an investigation of a hydrometallurgical process for the recovery of mercury from spent silver oxide button cells. The cell paste was leached in nitric acid to solubilize silver, mercury and zinc. The optimum leaching conditions, in which mercury is entirely converted to Hg2+ ions and, therefore, does not co-precipitate with silver chloride during treatment with potassium chloride solution, were 1.0 M HNO3, 45° C, 1 hour and 200 rpm. After the silver was removed from the solution, mercury was cemented out with zinc powder with an efficiency greater than 99%. In the cementation experiments, the amount of zinc powder, shaking rate, temperature and solution pH were investigated in detail. The mercury recovery (%) increased as the amounts of zinc powder and the temperature were increased. Zinc hydroxide was precipitated from the waste solution by the addition of sodium hydroxide. The Zn(OH)2 precipitate was then converted to zinc oxide. The proposed process is proven to be simple, straightforward and environmentally friendly.

Jan 1, 2011

By D. Mishra

Electric arc furnace dust (EAFD) generated during the recycling of steel- scrap is classified as a hazardous waste for landfilling. This is because it contains leachable heavy metals such as zinc, lead,... Recovery of these metals could result in both resources conservation and resolving waste disposal problems. A study of the thermal reduction of a sample of EAFD was carried out in an inert gas atmosphere using coke as a reducing agent. Preferential volatilization of zinc and lead was achieved during the reduction process at about 800 "C. More than 96 % of both zinc and lead were removed from the dust and were recovered in the condensates. The treatment residue was essentially composed of iron oxides and almost free from heavy metals.

Jan 1, 2002