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In the present work, the flotation behaviours of zircon, rutile and ilmenite using sodium oleate as collector in absence and presence of depressants were thoroughly investigated. The maximum in the flotation recovery of any of the above minerals falls within similar pH ranges. A range of inorganic and polymer depressants were examined in order to improve the separation of zircon from rutile and ilmenite. Optimum values of conditioning pH and depressant concentration to achieve maximum recovery and best selective floatability of zircon were obtained. Selective flotation of zircon from Ti-bearing minerals was anticipated from single mineral experiments under different pH values, depressant and collector conditions.

Jan 1, 2014

By Mohammad Noaparast, Hamed Haghi

"In this research work, it was attempted to reduce the iron contents (Fe2O3) in relatively low grade silica sample which was obtained from Shenin silica mine, using magnetic separation. The prepared sample contained 93.75%SiO2, 0.44%Fe2O3, 2.78%Al2O3, and 0.08%TiO2 and the Fe2O3 had to be reduced to less than 0.08%. Mineralogical studies and XRD analysis indicated the presence of Hematite, Pyrite, and Goethite as the major iron impurity phases. Mineralogical studies of polished and thin sections demonstrated that the degree of freedom of silica is more than 80% in -300+212 ?m size fraction. After primary stages including crushing, milling, scrubbing and de-sliming, various methods such as low intensity magnetic separation (LIMS), high gradient magnetic separation (WHGMS) and dry high intensity magnetic separation (DHIMS) were applied to find out that which process would be appropriate for the elimination of iron impurities from this sample. Different experiments were carried out on the product of wet rod mill and scrubber. However the magnetic field intensity of WHGMS was increased down to 2Tesla, and there was not any acceptable result in reduction of Fe2O3 content lower than 0.08%. Thereafter the product of wet rod mill and scrubber were dried and reported to DHIMS. In these experiments, maximum magnetic field intensity was 1.4Tesla. In this case very significant results were achieved, and Fe2O3 content of final product were reduced to less than 0.05% which meets glass manufacturing standards."

Jan 1, 2014

By H. R. Manouchehri

The importance of the grinding environment and its effect on sulphide minerals flotation behavior has been known for many years. The grinding environment may play a role in controlling fine and coarse particle flotation along with dissociation of different chemical species in grinding environment. Dissociation of different chemical species and ions within the process water may result from changing the grinding environment. The mining and mineral processing industry undertakes activities that may impact on water resources. These include use and storage of chemical storm-water management, process water management, mine dewatering and management of tailings. In mineral flotation understanding and controlling water quality is paramount important not only because of its effect on flotation but also with respect to control the quality of the water which is released to the environment. Releasing of different anionic and/or cationic chemical species in the process water results from the interactions among different mineral within the ore, process water, and the milling environment. In fact grinding mill acts as an electrochemical reactor which affects the flotation performances of different value minerals as well as the quality of the tailing products. An increasing in antimony content in process/discharge water at Boliden?s Tara processing plant in Ireland to above limitation level was reported in April 2010 which needed to be controlled. An increase up to 6 times of the permitted level was reported which needed an immediate action to control due to environmental considerations. Therefore attempts were made to detect why this higher amount of Sb is released and how to control and minimize its release to the process/reclaim water. This paper discusses how/why Sb content in process/reclaim water was increased by changing the mill electrochemistry and the strategies were taken into considerations to control it. Different strategies, including electrochemical controlling of the milling section, Fenton process, using Bauxsol in treating the process water, etc., have been considered and tested which are described herein. All strategies taken into consideration for solving the problem were successful which indicated good understanding of the issue and good decision making. Furthermore, for each solution the capital and operational costs were roughly estimated. Accordingly, the Sb content in process/discharge water was controlled to a value lower than allowed limitation, i.e., 1 ppm. Keywords: antimony, water contamination, mill electrochemistry, ag milling, grinding media, eh-ph, sulfide minerals, fenton process, bauxsol, lime addition

Sep 1, 2012

By C T. Dunbar, P A. Walker, G E. LeJuge

A programme of blast improvement was initiated at the Mt Whaleback iron ore mine by BHPIO management in early-1998. One component of that work was the need to improve wall control blasting practices to better achieve the designed pit slope elements. This paper describes the geological conditions in which pit walls are developed, the mine operating equipment, the blast design concepts applied to minimise blast damage, the techniques applied in an assessment of the blast performance and the operational procedures developed to ensure that the blast concepts are effectively implemented in the production environment. Substantial changes have been implemented in both technical and operational aspects of the mining operation in order to achieve the improvements in pit wall condition, in particular recognising the need for a more flexible approach to limits blasting in response to highly variable and complex geology. The benefits to the mine are not only an improved wall condition, but increased confidence on the part of mine management that mine plans may be implemented on design and on schedule.

Jan 1, 2001

By Michel Grenier, Robert Scott, Mahendra Gangal, Andrew Dasys

This research project which took place at Brunswick Mining and Smelting's Brunswick mine, was undertaken to assess the ability of new diesel engine technology to meet current and anticipated underground worker exposure limits to diesel exhaust contaminants. Concentrations of CO, CO2 NO, NO2 SO2 and respirable combustible dust (RCD) were measured in a remote mine area where a haulage truck was operating under simulated duty cycles. The 26 ton haulage truck was equipped with a 300 hp, electronically controlled engine. Fresh air was supplied to the area as per the MSHA certification document for this particular engine. Results showed that while the vehicle operated in a normal and realistic duty cycle, the concentrations of contaminants remained well below the ACGIH guidelines for the threshold limit values (TLV)for exposure. While operating at 630/0 of maximum horsepower (26 tons of ore in the dump), the time-weighted average exhaust gases concentrations (CO, CO2 NO, NO2 and SO2) never exceeded 150/0 of their respective TL Vs. ReD concentrations in this instance were measured at 0.59 mg/mJ or 39.30/0 of the exposure limit suggested by the Canadian ad hoc Diesel Committee. The Air Quality Index was 1.55 or 520/0 of the maximum suggested value for exposure.

Jan 1, 1994

By G. D. Rosales, P. F. A. Braga, S. C. A. França, C. P. Pinto

The growing market demand for lithium is mainly due to its use in the manufacture of batteries for electric or hybrid vehicles and portable equipment (smartphones, tablets, power tools, notebooks, etc.). Currently there is great interest in finding new sources of lithium and technologies for its utilisation. Li-S batteries have received attention due to their theoretically high specific energy density, which is 3 to 5 times greater than that of Li-ion batteries. Unlike Li-ion batteries, of which the main raw materials are lithium carbonate and lithium hydroxide, the main raw material for Li-S batteries is lithium chloride. The anode used in Li-S batteries is metallic lithium, produced by a molten lithium chloride electrolysis process. The extraction of lithium from pegmatites such as spodumene, previously abandoned in the 1990s for being uneconomical, has become attractive due to the increase in prices as well as the need for greater lithium purity of products made from lithium-bearing minerals. The main methods used for lithium recovery from spodumene ore include the sulfuric acid process, the alkaline process (lime or limestone as raw material) and the chlorination roasting process. Thermodynamic modelling using HSC software 5.1 was conducted to predict different reactions that could occur during chlorination roasting of the spodumene/MgCl2+CaCl2 system. Lithium extraction from the solid obtained after the chlorination roasting was also investigated. The results of thermodynamic analysis provided a better understanding of the chlorination roasting process for lithium extraction. Metallurgical tests with a mass ratio of 1:6 (spodumene:chlorides) and molar ratio of 2:1 (MgCl2:CaCl2) allowed over 95% recovery of the lithium contained in the spodumene concentrate. Keywords: Spodumene, lithium chloride, chlorination roasting

Jan 1, 2020

By Petr Dvorak, Jana Selucka, Hong Vu, Petra Starkova, Tomas Frydl

Waste, generated during high pressure leaching of lateritic nickel ores, contains about 50% of iron in form of magnetite but high chromium content ( *3%) does not allow its extensive utilization as the raw material for pig iron production in blast furnace. The chromium removal from the waste was carried out by two methods: (1) oxidative alkali roasting with NaOH and/or Na2CO3, followed by water leaching and (2) oxidative leaching in KOH sub-molten salts solutions. The results show that about 90.1% of Cr was removed when the waste was roasted at 900 °C for 3 h with 33.1 wt% of NaOH. The removal of 88.2% of Cr was achieved if the waste was roasted at 900 °C for 3 h with 40 wt% of Na2CO3. The sodium content in the water-leached residues was reduced from 5% to about 0.5% by reaction with CaO in aqueous solutions at 80 °C for 2 h. About 70% of Cr was removed if the waste was leached at 190 °C in 73 wt% KOH for 8 h.

Mar 1, 2017

By B. J. Moore

This Bureau of Mines publication reviews U.S. helium resources as of January 1, 1973. These resources, estimated to be 693.7 billion cubic feet, are broken down into four classifications, as follows: helium in storage, 34.9 billion cubic feet; helium in measured helium-rich natural gas reserves, 119.5 billion cubic feet; helium in measured helium-lean natural gas reserves, 62.8 billion cubic feet; and helium in indicated or undiscovered natural gas resources, 476.5 billion cubic feet. The helium in undiscovered natural gas is considered a national resource; however, this gas may not be discovered depending on many factors beyond the scope of this paper, and most of the helium in natural gas will be dissipated as the gas is consumed for fuel and other purposes.

Jan 1, 1976

By He De-wen

The influence of wastewater containing benzene from chemical industry by technology combined blow-off with Fenton reagent oxidation was experimentally studied. The present results suggest that the technology combined blow-off with Fenton reagent oxidation can effectively remove benzene pollutant in wastewater. The main factors that influence the removal benzene such as temperature and blowing time and volume, pH and reagent dosage of H2O2 and Fe2+ are studied and the optimal experimental conditions are as follows: time 20min, temperature 40i, air-blowing volume 0.4L/min, pH value 5, and H2O2 and Fe2+ dosage 2mL/L and 200mg/L respectively. Under the above conditions, benzene pollutant can be removed up to 97%. Compared to other removal ways of wastewater containing benzene, the technology combined blow-off with Fenton reagent oxidation is more effective and has the advantage of high speed.

Jan 1, 2009

By A. Ouchi

This paper presents ground control best practices in weak rock environments including the "Unsupported" Weak Rock Updated Span Design Curve and awareness pertaining to the potentially detrimental effects of using resin grouted rebar in weak rock masses and the false sense of security that the use of resin grouted rebar may instill. Ground support is almost always used in weak rock environments, though the type of support used can vary widely. The development of the Weak Rock Updated Span Design Curve by the addition of 463 case histories of RMR76 values ranging from 25 to 60, has also been calibrated to four different support categories; Category A: Pattern Friction Sets, Category B: Pattern Friction Sets with Spot Bolting of Rebar, Category C: Pattern Friction Sets with Pattern Rebar Bolts and Category D: Cablebolting, Shotcrete, Spiling, Timber Sets or Underhand Cut and Fill. Design of underground man-entry type excavations in North America relies heavily upon empirical analysis. This design requires a higher Factor of Safety than other non-man entry type excavations. A comparison of the calculated ½ span failure Factor of Safety between all the categories is also presented.

May 1, 2009

By Jeffrey A. Aldinger

This U.S. Bureau of Mines report presents an analysis of surface coal mining accidents involving mobile equipment for the years 1989 through 1991. Mobile equipment is defined as haulage trucks, front-end loaders, bulldozers, scrapers, and road graders. These five pieces of mining equipment accounted for 20 pct of all surface coal mine accidents and 41 pct of the fatalities. The general discussion of these accidents covers the accident causes, the primary activity of the accident victims, and other contributing factors. A more detailed analysis of accidents associated with each piece of mobile equipment is also provided. This report will provide mine managers and mine safety personnel with a better understanding of the hazards associated with mobile mining equipment. It identifies where improvements in mobile equipment safety can be made and those areas requiring additional safety emphasis, such as safety training, work procedure changes, or engineering changes to the equipment or work environment. The analysis was performed by a team of researchers using accident data and narratives provided by the Mine Safety and Health Administration.

Jan 1, 1995

By C K. McKenzie

As more and more mining operations around the world either switch to, or trial, electronic initiation systems, the breadth of knowledge and experience regarding their effective application has widened considerably.In South America, for example, there is a strong perception that in order to achieve the finest possible fragmentation, very short electronic delays must be used between successive holes within a row. Limited field studies involving measurement of fragmentation have been conducted to support that paradigm and there are few long term studies which have been strongly supported by measurements of productivity either in the pit, in the plant, or in the leaching pads.On the other hand, some well documented studies have been conducted in North America, showing not only the impact of delay timing on fragmentation but also the effect on semi-autogenous grinding (SAG) mill productivity over extended periods of in excess of 12 months. To date, those studies suggest that optimum timing is considerably longer than the times commonly used in South America.This paper explores the current knowledge of the effects of delay timing on issues ranging from size distribution to vibration impacts in pit walls, to vibration and overpressure impacts in surrounding communities. It also explores how fragmentation modelling can be adapted to reflect fragmentation trends that have been reported in various technical conferences around the world.

Nov 8, 2011

The general types of industrial behaviour of liberated valuable sulfide minerals in the 0 - 10 ¦m size fraction are described and tests to explore on site at a concentrator the general nature of any deficient behaviour are discussed. In addition, the general types of behaviour of the gangue minerals in this size fraction are also described in terms of their mechanisms for recovery. These behaviours are also discussed in terms of the type of grinding device and grinding environment in which they were produced and the target grinding product size. Major recent improvements in the industrial capabilities of grinding devices are discussed.Present difficulties in characterisation of particles in the 0 - 10 ¦m range are described and desirable improvements for the future are outlined. Further, desirable improvements for industrial processing of valuable minerals in this size range are discussed along with some remedial actions.

Jan 1, 2005

By T. E. Swigart, C. E. Beecher

The Federal Government, as the largest lessor of oil and gas lands in the United States, is vitally interested in the conservation of those resources. This manual has been prepared at the direction of the Secretary of the Interior to call the attention of lessees of public oil and gas lands to the most common oil and gas field wastes and the best methods of preventing them; to outline the policies of the Interior Department on field operations; and to give information as to how the "Operating Regulations" of the department will be interpreted by the Bureau of Mines. The oil industry has progressed steadily. Present operating methods are much more efficient-and less wasteful-than those of a few years ago; moreover, the art of producing oil and gas is continually advancing. Public interest requires that improved methods, which will result in obtaining the greatest possible amounts of oil and gas from the natural deposits, shall be developed and used. Part I of this manual points out types of oil and gas wastes and suggests, in detail or by reference, the most practical and effective methods in current practice for stopping these wastes. Throughout Part I the department's operating policy is given, with interpretations of the "Operating Regulations" for enforcing every practical measure of conservation. Part II comprises the revised "Operating Regula-tions" which supersede all previous regulations and will govern future operations on public lands; it will be found in the pocket in the back cover of this bulletin.

Jan 1, 1923

Continuous improvement in environmental management assists in the achievement of sustainability goals for the processing of minerals. The use of regular internal environmental audits (scored or unscored) which form an integral component of an Environmental Management System (EMS), provide demonstrable evidence of this improvement. Case studies are presented for a number of major coal mines in the Hunter Valley, where regular internal environmental audits have been undertaken every two to three months, over periods varying from 18 months to five years. Examples of the benefits of improved environmental performance (driven by the audit process) to sustainable development are provided.The auditing process as described here for coal mines, and coal handling and preparation plants, is equally applicable to the processing of other mineral ores, metalliferous mines, quarries, and oil and gas projects.

Jan 1, 2004

By W. H. Van Niekerk

The metal zinc has been around since only about 1400 AD. This may sound like a long time, but when compared to fellow base metals copper and lead, which were discovered in 5000 and 4000 BC respectively, it is evident that zinc is a fairly new kid on the block. This may also be the reason why many new facts and benefits of zinc are still being discovered. For instance, it has been discovered only in the last few decades that virtually no life on earth is possible without zinc. In this address it will be shown that zinc is not only very useful to mankind, but is in fact vitally important for all forms of life. It will be shown that zinc is natural, zinc is essential for life, zinc protects, zinc contributes to the well-being of society and that zinc is fully recyclable. It is therefore hoped, that by the end of this address, zinc will no longer be viewed only as the metal that is responsible for the nice colour of roofing sheets and steel buckets, but may indeed be man?s best friend.

Jan 1, 2005

By C. E. Jordan

The Bureau of Mines investigated a simultaneous elutriation and flotation technique for separating polyethylene terephthalate (PET) from polyvinylchloride (PVC). The Tuscaloosa Research Center, through a cooperative agreement with a recycling company, devised an elutriation-flotation method for beneficiating the mixed heavy plastics portion of municipal solid wastes which is composed of polystyrene (PS), PET, and PVC. A sodium carbonate brine was used to remove the lighter PS from the heavier PET and PVC. Over 98 pct of the PS was recovered in a high purity PS concentrate containing 99.7 pct PS, The remaining PET and PVC mixture was washed to remove the brine salts that would be harmful to the flotation process. The clean PET and PVC mixture was conditioned in a solution of 45 g/t gelatine and floated in a short (l-m) column flotation cell in an upward flow of water. In a single flotation step, over 75 pct of the PET was recovered in a high purity product containing 99.8 pct PET. The bubbles attached to the PET lowered the effective density of the PET-bubble agglomerate and allowed successful separation of these agglomerates from the PVC plastic pieces. This method separated two-thirds of the mixed plastics fraction into high purity PS and PET products suitable for recycling and left only one-third of the plastics in the mixed plastics product.

Jan 1, 1992

By Allan MacRae

Freeport-McMoRan Inc. operates an ISASMELTTM furnace for the smelting of copper concentrate at the Miami Smelter in Claypool, Arizona. In May 2017, the furnace was restarted after incorporating newly designed copper cooling elements from just above the tap hole to the underside of the roof. The objective of the improved cooling design was to extend campaign life by eliminating existing failure mechanisms with the wall refractory. In addition to upgraded bathline coolers and complete coverage of the gas offtake transition, or ‘kettle’, with plate coolers, a novel arrangement of coolers was installed in the remaining freeboard area. The shell required significant cutting and re-stiffening, as well as extensive modification of the cooling water piping. Based on performance observed to date, it is expected that smelter throughput will be increased due to extended ISASMELTTM refractory campaign life.

By L. R. Plitt

A series of experiments were carried out in an effort to develop a universally applicable mathematical model of the hydrocyclone classifier. The design and operating variables studied were: cyclone diameter and height, the inlet, vortex finder and apex diameters, the feed pressure and the solids content of the feed slurry. The model consists of four basic equations which express the cut size ( dso), volumetric split between overflow and underflow, volumetric throughput, and sharpness of separation in terms of the operating and design variables. Although empirical, the model is nevertheless in general agreement with fundamentally derived models. The model clearly 1•eveals the effect of the major variables on the operation of a hydrocyclone. Because of its broad data base and the inclusion of all the major variables, the model may be used without experimental data to predict the operation of cyclones over a wide range of different operating conditions. With operating data, the equations may be modified to serve as an operational model.

Jan 1, 1976

By Robin Sheremeta

Fording Greenhills first acquired GPS (Global Positioning System) technology with the commissioning of a GPS-based dispatch system in December 1994. The second exposure to satellite technology came with the conversion of the conventional optical survey system to a high-resolution GPS system in June 1995. In September 1995,a GPS-based grade control system was tested on the largest shovel (Marion 301 — 58 cubic yard).In January 1996, the system was added to all of the cable shovels (2 P&H 2800s). All three applications of GPS at Greenhills are fully operational and producing positive results. This paper will focus on the practical application of GPS in a mining environment and the effect that GPS technology has had on the Greenhills Mine.

Jan 1, 1996