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By Yonghong Qin, Songbo Ma, Qi Zhang, Peng Gao, Jianwen Yu

Herein, the coal-based reduction was proposed to utilize the ferronickel slag of Jingchuan company. An excellent index with metallization rate of 99.22%, iron grade of 77.91%, and iron recovery of 92.79% was obtained at carbon addition coefficient 2.0, reduction temperature 1573 K, reduction time 60 min, the particle size of coal and ferronickel slag − 2.0 mm, and CaO content 15%. The 2FeO·SiO2 was reduced to Fe and SiO2 with the increase of temperature. The CaO could promote the reduction of iron oxide. Most of the sulfides (Fe, Cu, Co, and Ni) in the sulfonium were reduced to metal. The reduction degree increased with the reduction time and reduction temperature. The higher reduction temperature represented the higher peak value of reduction rate and the shorter time of reaching the peak value. The isothermal reduction process included three stages: early stage, middle stage, and late stage. The mechanism function were f(α) = 1/2(1 − α)3, f(α) = 3/2(1 − α)4/3[(1 − α)−1/3 − 1]− 1, and f(α) = 4(1 − α)[− ln(1 − α)]3/4, respectively. The activation energy of three stages was 183.498 kJ·mol−1, 420.077 kJ·mol−1, and 656.619 kJ·mol−1, respectively.

May 24, 2022

By A. J. Teske

Sustainable Development is a very broad initiative in the mining industry, with major components running over the entire life of the mine. It likely commences with pre-exploration permitting and continues to post-mining final closure and possible land reuse. Most major mining corporations embrace the sustainability initiative, either out of a sense of social responsibility or out of necessity in order to continue doing business. But many may view the overall initiative as an added ?cost of doing business.? In many elements of sustainability, there clearly can be added cost ? some as simple as complying with self-imposed sustainability reporting. Fortunately, one major element of sustainable development can clearly be shown to reduce costs ? energy resource management. This paper will describe how the mining industry sustainable development effort differs from other industries, but can benefit from their experience in energy resource management. The mining industry can utilize proven methods from other industries to further their energy management efforts. In addition, many of the resources developed and employed to promote better energy resource management in non-mining industrial settings will be listed.

Jan 1, 2010

By W. M. Tupper

[The two types of sulfide deposits in the Bathhurst Newcastle area are; (a) epignetic fissure deposits, and (b) massive sulfide deposits. Geological evidence has been variously interpreted to suggest a syngenetic origin, a source bed' origin, or a magmatic hydrothermal origin for the massive sulfide deposits. Sulfides disseminated through the black shales and argillites of the host rocks are enriched in S32 (mean value 22.34, S34. = 5.8 per mil) relative to the meteoritic standard of 22.21, and have a broad spread in range of values. S32/S34 ratios of sulfide minerals from the deposits occur in two distinct groups. The massive sulfide deposits exhibit ratios between 21.88 to 22.05, while the fissure deposits exhibit ratios between 22.18 and 22.21. These results suggest two separate sources for the sulfur, each, however, resulting in magmatic hydrthermal deposition because of the narrow spread of ratios in each group. Granite intrusive into the host rocks of the sulfide deposits have a mean K/A age of 386 ± 10 M.Y. Lead minerals in the sulfide deposits have a mean nodel lead age of 370±20 M. Y. Thus the lead minerals and the granite bodies were emplaced during the same major orogenic event. Sulfide minerals from magmatic hydrothermal deposit have a very narrow range of S32/S34 values, as do those of the Bathurst area. It seems reasonable, therefore, that well homogenized magmatic hydrothermal solutions are the most logical source of the sulfide deposits. Furthermore, the homogeneity of the lead isotopic abundance data gives strong independent evidence that the ores are of a magmatic hydrothermal origin.]

Jan 1, 1960

By Rick Frechette, Greg Nelson

"The 2018 Elko Roundtable was held at the Red Lion in Elko, NV on March 15, 2018. The gracious host was once again Knight Piésold. Attendance was robust with representatives from more than 14 mining properties across Nevada representing nine corporations. Total attendance was at its highest in almost a decade. A high level of interest was also gauged by the number of companies with multiple attendees.The topic of water in mining was clearly a factor in creating the large show of interest. In terms of industry trends that are tracked annually, this topic had been absent from the list for more than 10 years (Deloitte, 2018) but was squarely planted there this year. And deservedly so. Three attending companies are signatories of the International Council on Mining and Metals (ICMM) which espouses a firm stance on water stewardship (ICMM, 2017).How’s the water?It is reported that water scarcity affects more than 40 percent of the world’s population (Deloitte, 2018). Consumption of water in the United States, based on the last detailed census, entails only 1.5 percent usage by the mining industry. The largest users are reportedly thermoelectric power and irrigation, combining for more than 75 percent of the U.S. consumption. During the prior census period, water usage at mines was up dramatically (USGS, 2014).Mine water source usage is primarily a mix of ground water and saline or fresh surface water resources. Over the previous period, saline sources experienced the greatest percentage in growth as a mine water source, nearly doubling in use. Nevada ranks second as a state nationally in mine water consumption. California is the leader, and Nevada is immediately followed by Utah and Alaska (USGS, 2014).Water rights in Nevada and the ongoing litigation at the state level, particularly over the Humboldt River basin, have elevated the concern over the supply of water and have raised the interest regarding the topic of water across the mining industry as well as within other industries.The Elko Roundtable meeting began with a safety share and introductions, and included each attendee mentioned a water problem or solution that he or she would like to discuss during the day. An interesting list of subtopics was developed from this round robin and yielded the following most common themes:• Mine pit dewatering during operation and pit wall stability.• Draindown from tailings dams and heap leach pads and dealing with this at closure.• Post closure pit lakes, pit lake water quality and associated water rights."

Dec 1, 2018

By M. L. Brashears

Pine Point Mines is located in the Northwest Territories of Canada, about 500 miles north of Edmonton, Alberta (figure 1). Lead-zinc ore is found in numerous localized deposits along a generally east-west trending reef of Devonian dolomite, about 5 miles south of Great Slave Lake. A pumping-test program was carried out in 1968 to guide the design of dewatering systems for several open pits that are partially or wholly below the natural ground-water levels. The hydrogeologic conditions, methods employed and results obtained are discussed.

Jan 1, 1971

By D. M. S. Bhatia

Twenty-six insitu analyses of cubic galena crystals from a Mississippi Valley-type deposit were undertaken with a laser microprobe spectrograph to study the variation of nine trace elements from the crystal center to its periphery, both along the diagonal and vertical. The general trend is an increase in the concentrations of Ag, Ga, Ge, and In with As showing the opposite trend Bi, Cd and Sn did not show any pattern. Sb was not detected. These variation patterns nay serve as a model for similar studies of other Mississippi Valley-type deposits.

Jan 1, 1984

By R. Herrera-Urbina

Measurements of the electrophoretic mobility of bastnaesite in aqueous solutions of sodium nitrate reveal that the isoelectric point (iep) of this cerium fluocarbonate occurs at about pH 9.3. These results also indicate that the pH affects significantly the electrophoretic mobility of bastnaesite, which becomes more positive as the pH decreases and more negative as the pH increases from the iep. Computations of solid-solution equilibria for the bastnaesite-H2O system closed to the atmosphere as a function of pH indicate that cerium fluoride precipitates in acidic solutions, whereas cerium hydroxide precipitates in alkaline solutions. When the initial amount of bastnaesite is fixed at 0.05 wt.% (the solids concentration used for electrokinetic experiments), these computations reveal that bastnaesite is the only solid phase in the pH range from 5.75 to 8.55, it coexists with CeF3(s) between pH 5.22 and pH 5.74, and with Ce(OH)3(s) between pH 8.56 and pH 10.12. Cerium fluoride and cerium hydroxide are the only solid phase below pH 5.2 and above pH 10.2, respectively. According to these computations, the dissolution-precipitation processes that occur when bastnaesite is equilibrated in aqueous solutions at different pH values determine the solid phases present in the system. In turn, these processes must affect the electrokinetic potential at the solid-solution interface, and they must be considered for explaining electrokinetic measurements as a function of pH when bastnaesite is the original solid phase in aqueous suspensions.

"It’s been 80 years since Charles Warman invented the iconic Warman slurry pump, a pump that revolutionized the mining industry and continues to push the boundaries of pump performance to this day.In honor of this legendary brand, Weir Minerals hosted an event at the end of May in Kalgoorlie, Western Australia. Throughout the evening, attendees relived Warman pumps’ history and gained an insight into some of the future innovations planned.“It was a privilege to share this special night with some of our key customers, past and present employees, and members of the Western Australian School of Mines,” said Ricardo Garib, divisional president of Weir Minerals. “Warman is one of our leading brands. It has truly shaped the mining industry over the past 80 years and is a product we are all very proud of. The Warman pump, invented to solve high wear issues in slurry pumping, created a thriving industrial business that is now the cornerstone of Weir Minerals with more than 8,000 people, and more than 150 manufacturing and service centers across the globe.”Always inventingCharles Warman invented the Warman slurry pump in Kalgoorlie in 1938. It was a hardwearing slurry pump that used replaceable liners and a replaceable impeller, something that had never been done before.“Charles Warman was a visionary and an innovator. The use of rubber lining in the pump was groundbreaking as it reduced total ownership costs, was safer to handle and offered extended wear life in many abrasive slurry applications. It is a great example of solving customer problems with material science, and is still taught in universities today,” said Marcus Lane, global product manager for centrifugal pumps at Weir Minerals.It was quickly adopted throughout the goldfields in Western Australia and by the 1950s, as customer demand rose, Warman expanded his business by opening offices in Sydney and Perth.During the 1960s the rapid growth of the business continued with manufacturing and sales outlets established around the world. The Warman Series ‘A’ pump was accepted and became a world leader in its field. Further work on the Warman AH pump resulted in the development of interchangeable metal and rubber wearing components."

Jan 9, 2018

By Güldane Atesoglu, İsmail Atilgan

The changes in the elemental contents and the structural properties of chalcopyrite concentrate when roasted were studied, and the main reactions contributing to the leaching process revisited. Firstly, TG/DTA measurements were performed to identify the roasting temperatures that influenced the type of species reacting with sulphuric acid leaching liquor. The temperatures of main reactions, whose output may affect the subsequent leaching process, were analysed for the concentrate at hand, and concluded to be generally lower than those reported in literature. Secondly, the obtained results were confirmed by images and XRD measurements on the roasted concentrate at temperatures in between 350 and 600 °C with increments of 50 °C. Finally, the leaching behaviour of the roasted specimens in a stirred sulphuric acid solution examined and the Cu/ Fe selectivity investigated that the maximum Cu/Fe ratio in the pregnant solution would nearly be achieved for the roasting temperatures lower than 500 °C, since the oxidation temperature of iron sulphate is found lower than that of copper sulphate.

Aug 11, 2022

By T. T. Toomver

The evolution of Inco's Selective Reduction Smelting Process as practised today is described, beginning with the initial laboratory experiments on small samples to the processing of large bulk samples through pilot plant equipment. For both the Guatemalan and Indonesian (Soroako) ores, the initial screening tests using hydro-, vapo-, and pyro-metallurgical processes showed that the latter was the most promising both metallurgically and economically. Later, larger scale tests confirmed the earlier testwork.

Jan 1, 1979

By T. H. Bagan

The Sixteen-to-One Mine was originally designed and operated using Blasthole Stoping with end slicing as the primary mining method. This method changed to Modified VCR Stoping in response to efforts to control dilution. The new method combines Blasthole Stoping with shrinkage methods, pillars, and reduced sublevel intervals to provide the most practical dilution control avail- able for low cost bulk mining.

Jan 1, 1987

By Dominique Francois-Bongarcon

The world mining industry is facing a severe recession. Thus, it is time to recall the value of geostatistical methods which were formerly developed as a money-saving and productivity-increasing tool. The situation has worsened, but the techniques of geostatistics have dramatically changed. Up to millions of dollars can be saved during exploration with simple use of variograms; then, during reserves estimation with kriging methods; and finally, with the parameterization of reserves, when evaluating a project and optimizing its global mining parameters.

Jan 1, 1983

By P. E. Damon

An arsenal of isotopic techniques is avail-able that can date the full range of hydrothermal ore deposits. The following are prerequisites for ideal results: (1) Careful collection of samples that are related to the event in a field and process context; (2) Optical examination of the component selected for dating to be sure that it has not been altered; (3) Careful preparation of a pure component of the sample selected for dating; (4) Precise and accurate measurement; (5) Knowledgeable interpretation of the data with reference to decay systematics, properties of the component analyzed as well as the field context and thermochemical environment of the ore process.

Jan 1, 1992

By J. Rao Mokka

Extensive exploration has resulted in delineation of a massive sulfide district on the north flank of the east-central Alaska range. The district covers approximately 400 square miles and contains numerous stratiform; transported and some replacement type sulfide deposits ranging in size from less than 1 million tons to 20 million tons. Five types of ores were sampled for the study. Mineralogical analysis revealed that the minerals are too fine grained for conventional grinding and beneficiation. Hydrometallurgical studies were con-ducted using ferric chloride as a lixiviant. Ore microscopic studies as well as electron microprobe analyses of minerals in the raw samples and leach residues explained the low recoveries for certain elements as well as sources of impurities that need to be eliminated from the process streams.

Jan 1, 1991

By F. Alsobrook

Industrial minerals are receiving increased attention by metals, coal and other companies seeking to diversify and stabilize earnings. Each industrial mineral has a unique set (and sub-sets) of business dynamics, however, and the diversity can present a bewildering maze to the corporate planner. Shrugging off this complexity and relying on serendipity for entry opportunities often results in unsuitable acquisitions. An effective alternative used in exploration can also be applied to strategic planning. By providing focus and direction, this flexible methodology can prevent wasting corporate resources on random pursuits and result in a quicker, more satisfactory achievement of diversification goals.

Jan 1, 1990

By David N. Hedges

This paper discusses the actual recovery and installation of a longwall in a bituminous coal mine in Western Pennsylvania. The coal bed mined is in the Lower Freeport seam which averages 42 inches (1.07m) in height locally. Drainage from the mine is approximately 3.5 million gallons of water per day (13.25 million liters per day). This water deteriorates the mines predominately fire clay bottom making it extremely difficult to move equipment. Support removal is accomplished by pulling the 6 ton (5443 kg) shields out under their own hydraulic power and transporting them by track over four miles (6437m) co the next longwall panel. This paper also discusses the changes that will be made to aid in the succeeding longwall recoveries and installations.

Jan 1, 1984

By Simon E. Rodriguez

This paper presents sulfur isotope data obtained for the deposits and country rocks of the Bailadores and Aroa Mining District, Venezuela. The study is a part of an extensive geochemical investigation of the mineralized belts that has as their aim the elucidation of the genesis of ores. The Bailadores deposits are located at about 600 Km. west-southwest of Caracas, or about 10 Km. southeast of the Town of Bailadores, Merida State (Fig. 1). The mine concession is held by the Ministry of Mines and Hydrocarbons (De Lima I, De Lima II and La Cascade areas). In a straight distance the mine is about 90 Km. southwest of Merida, the capital of Mérida State. From Mérida to Bailadores, through La Victoria and Tovar, it takes 3 hour by car. From Bailadores to the mine site it is about 40 minutes by jeep. The Aroa deposits are located at 4 Km. east of Aroa Village, Yaracuy State, about 220 Km. west of Caracas. It is 83 Km. from San Felipe, the capital of Yaracuy State to the mine (Fig.2). The mine is about 600 m above sea level, situated on the northern foot of the E-W trending Andes. The topography of the mine are shows a mature stage and is somewhat rugged. As the climate is warm and humid, the area is thicky covered with jungle.

Jan 1, 1974

By J. Platt

Debate over acid rain legislation has presented a moving target for coal and utility company planners attempting to figure out how legislation will affect their business environment. In spite of disagreement among experts, the prospect for continued change, and persistent --perhaps even growing --uncertainty, a great deal has been learned about coal market dynamics. This paper reviews progress and describes some of the major problems and controversies.

Jan 1, 1990

By E. A. Devuyst

Metallurgical processes involving the use of cyanide such as gold cyanidation, metal plating and flotation, generate effluents containing cyanide and cyanide in complex combinations with heavy metals in quantities exceeding those regarded as being safe for discharge into streams. A new process for destruction of free and complexed cyanide and related-species in wastewaters has been developed at the Inco research laboratories using sulfur dioxide, air and lime. High reaction rates are obtained in the presence of a small amount of copper which acts as a catalyst. Cyanide species can be reduced to as low as 0.1 mg/L in a very short treatment time. Examples of treatment of gold mill effluents and barren slurries, plating rinse waters and flotation liquors or tailing slurries are given.

Jan 1, 1982

By L. Nahai

In an exchange of views with the Program Chairman for the Technical Session on Industrial Minerals and Investment in Foreign Countries, it was agreed that it would be more interesting to approach the problem of mineral investment in foreign countries in a more general framework and not confine it to industrial minerals. Therefore, this Bureau of Mines report is proposed to examine current attitudes toward investments in foreign mineral resources and restraints that they impose on investments necessary to assure supply for future global mineral needs.

Jan 1, 1976